Multiple MacBook issues...

Im using MacBook Pro Mid-2010 (7,1) and I have more issues with it... First issue I mentioned is that RAM memory amount is changing... I have 2 x 2GB but sometimes it's showing 2GB (Same on BootCamp as on the Yosemite)...

So I opened my MacBook and removed one stick top bank0 and left the other one in bottom bank1... MB started as usual, showing 2GB (as expected)...

Then I turned off MB and moved same RAM stick into top bank0 and it worked...Done the same with another stick and it' works... I have never changed RAM sticks since I got MB (It's by Samsung - M471B5673FH0-CF8)... So sticks are working individually, but not together... Maybe this is issue from the beggining, but I didn't mentioned it before... Before that I got a problem with wake-up from sleep (on BootCamp and OSX). I've done hard reset to get it work (I think I lost RAM memory after this, not sure..)

After all that I got back to Yosemite and started to type my password (starting with uppercase A and rest are the numbers) and it told me that password is incorrect... I tried again again and again (using left shift for first uppercase password letter)... Then I was like OK, so I used capslock-on (...typed) capslock-off and it was correct...I totally forgot that I was unable to login using L-Shift but it happened again while typing something in the browser...

So I found out that something is wrong between L-Shift and L-Alt (Option key)...

So here is the example whats actually happening... When I press L-Shift, it is pressing R-Shift (as expected), but also pressing L&R-Alt buttons???!!!

Screenshot is the same when I press L-Alt (Option key)... 😟 😟 Shift=Alt f**k

The right side of the keyboard (R-Shift,R-Alt) and all other buttons on MB are working correctly, so there is only something happening on the left side...

Right side works, but it's really uncomfortable for my left hand to type without left shift.😟

Just to mention that before I got similar issue (alt buttons stuck) and I was unable to type desired letters - I restarted MB and that was gone...

Ok, preety long topic, but I wanted to explane whats happening... Guys I appreciate every reply that can solve any of those nightmares! 😟 Thanks.

Edit: done PRAM and SMC reset (nothing happened)