Don't laugh, but I've.... I've never had a mouse with side buttons before
A of mice are ambidextrous (probably why I had no issues), though you can get left handed mice with side buttons. (just browsing on Amazon)
This is the only mouse I have ever had with extra buttons. It is kinda of neat in mouse driven games. Allows me to assign something like health and mana pots to them. I actually am not really that into the mouse. The extra buttons are nice. Not really a deal breaker loosing them. I was using a wireless keyboard and mouse up to this month. My mom needed that for her T.V. computer setup I put together for her. So I used this mouse. I had tried it previously and relegated it to a discard bin with all my extra keyboards.
It turns out it was my only working extra mouse. I have a mouse in pieces I could try and reassemble.
I have been looking up devices. Did some research and think I would prefer the cherry mx brown switches to all the other cherries, Tek Syndicate has a tolerable video on the differences in some switch types. I don't think I have used a mechanical keyboard in decades. Never actually sure what I am using. Pretty certain it isn't mechanical. It tends to be the cheapest thing I can get my hands on. I also found that there are left handed mice (poor mice. all the tests it must have to go through just to find out southpaw specific data). I am interested in the ergonomic ones. There doesn't really seam to be any "quality" options though. Just pricey ones.
I did see the left handed mice with extra buttons right before returning to here. I don't know if investing in all new mice is a good plan yet. Especially as I increased my computer count to two on this desk. I still haven't found a good peripheral to buy for the pi to replace its keyboard and mouse. My desk is getting so crowded. Even the shelves I took from my brother's room and placed on my desk aren't providing enough room. there must be some scientific law that saws "something will always fill a vacuum", as any free space I create quickly is filled by another item that it is extremely important that it goes there.
Edit:
I finally remembered. It was "Nature abhors a vacuum".
I was finally able to reasemble the mouse. I just had to stop trying to keep it from braking and just take the chance and slam the parts together. I think I spent an entire hour, total, on trying to get that thing back together.
I was rather lucky. After I switched out my wireless mouse for it my mom accidentally spilled liquid on it. I took it apart to dry it out. I haven't had issues with getting mice back together. It always worked in the past. This time it didn't. Once I was sure the mouse was thoroughly dry I tried to reassemble it. It wouldn't go back together for anything. That is how I ended up using the mouse with the two extra buttons.
Now that it is back together I will use it until I can get another good mouse. (it isn't going to be any time soon. I spent every penny I had this month and more. Mostly on getting my house ready for summer.)
Edit:
Thought about it some more. If my arms are supposed to be straight out from my shoulders. Then my strain issue might be a lot more do to the position and size of the keyboard then the position of the mouse.
When typing my hand are extremely close together on a standard keyboard. For them to be shoulder width apart my right hand would have to be about where my mouse is now, and they entire keyboard need moved to the left by at least six inches. I don't know how to measure it properly. It seems like my hands would need to be 21 inches apart to be properly positioned. That is a lot longer then my current keyboard.
I think it is the position of the keyboard that is the biggest issue. I keep it in a position where both hand can reach the touch type positions on the keyboard. I think for video games it might be better to move the key board to the left a ways. For typing it might be better to use a split keyboard or possibly two keyboards end to end if there is enough room.
Will definitely take more research.
Edit:
Found a site that has lots of tips and instructions for keyboard and mouse placement and user posture. It is proving to be a lot more thorough then other information sources have been.
I still need to do further research and strategy costs comparisons to see what they best setup for me would be. I am learning a lot of new stuff today.
Edit:
I went back to left handed mouse. This time I am trying it out without reversing the mouse buttons. It is going the same. This alternative was recommended somewhere. I just can't remember where.
I found using the number pad is much simpler for games that use the number row a lot. I used to assign those keys to q,w,e,r,a,s,d,f,z,x,c,v depending on how many keys bindings were available. It works really well for w,a,s,d movement as well. It might not work as well on games that use both. Those usually have alternative ways of accessing the number bar though.