i've been playing guitar for about a year and bass for a year and a half, and as i've started to play guitar more often than bass i've been noticing pains in my fretting hand's wrist.

the point of pain is right where the 3 tendons from my index, middle, and ring fingers go from my knuckles to my wrist (i'm skinny so i can tell). it hurts when (hand on table, palm facing up) i pull my hands towards me.

i asked the anatomy/biology teacher at my school and he said it could be a cyst on a nerve in my wrist which kinda freaks me out, but i hope its not that serious.

if i stop playing for 2 ish days it kinda goes away, i'm self taught but i don't think my technique is that horrible, but what should i do? should i get an evaluation or something by a guitar teacher to help fix my technique?

any help would be much appreciated.
the minimalist σƒ τλε τρπ βπστλεπλσσδ
try going throw a couple of 3 string excercises that span 5 frets, or sweep the pentatonics, really just stretch your hand a bit before you really start playing, along with all your other warmups
"If you're looking for me,
you better check under the sea,
because that's where you'll find me..."
Yes you really should stretch and warm-up before you play.
But I think your problem is more than that.
If you don't know much about technique, I'd just go look at the first section
of any "How To Play" books, they all show how you are supposed to play.
You may just have bad wrists man. Also, any bending in your wrists for a long time can cause carpal tunnel.
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It is likely you're playing your guitar at too much of an angle/not enough of an angle, or too high/low. Sometimes some people get wrist and hand pains if the neck of their guitar is too thin/thick too.
Yes, I know everything. No, I can't play worth a damn.
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FreePower has a couple lessons on core technique, and they are good examples, hit them up
"If you're looking for me,
you better check under the sea,
because that's where you'll find me..."
do you think the season change in air temperature and pressure would have any hand in the sudden wrist pains?
the minimalist σƒ τλε τρπ βπστλεπλσσδ
Try some 4 note per string warmups, alla Rusty Cooley, there's a Guitar Pro excercises thread in Advanced Techniques that covers a few.

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