My mid-2014 MacBook Pro trackpad is not working and my keyboard is lagging too!

Hey all, so this is irritating. My trackpad has not been working for a while and now I've noticed the keyboard is becoming progressively more unresponsive.

I've reformatted the hard drive and reinstalled Mac OS but to no avail. I read on previous forums and posts that it's possible that the battery swells and presses against the connector for the trackpad but before I go and have this replaced, I want to get some idea if its possible that that is what's affecting the keyboard too.

As we dont have Apple Stores in South Africa, (and our authorized Apple dealership here is ludicrously expensive), I cant simply take it in to see a Genius for diagnosis.

Any help with self diagnosing these issues before just having parts replaced would be super helpful!