Been playing for about 2.5 years. When I make a fist, a small bump appears somewhere above my trapezoid and trapezium bones. When relaxed, there is no bump.

I had a scaphoid fracture 2 years ago. Don't remember if i had the bump then.

Could this be related to some bad guitar playing technique of mine?

Thank you
Not to be an idiot but...a muscle..?
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Unless you're playing with some positively horrendous technique, odds are no. Still couldn't hurt to get it looked at though.
Prob a cyst (bible bump), if it is you have 3 options, smash it with a book and it will pop it and will go away, have it drained with a needle at the docter, get surgey if they keep coming back

I had one, smashed it with a book, Gone. (hurts a fsking lot >_>

BUT go get it checked it if hurts or anything and are worried.
Quote by Lewadra
Not to be an idiot but...a muscle..?

Probably. Not a bone, for sure.

Cysts are supposed to stay up even when the hand is relaxed, aren't they?

As far as playing techniques go, even after seeing many tutorials, I have observed that A shaped barre chords seem to require some force whereas E shaped ones are damn easy for me. But my strings are old and I have tuned them up a few times since they go out of tune after a fair amount of playing. COULD be because of that,though I'm not sure.

Other than that I don't know.

I just wanted some opinions in case anyone has faced this problem before.
i think the main question is, does it hurt?

if the answer is no: i wouldn't worry about it.
if it starts to hurt, then get it looked at.

Also, don't worry too much about having horrendous technique. Guaranteed there are a lot of brilliant guitarists out there who use technique way worse than you, and probably play better than both of us!