Things that we use for these types of things if you think it is muscle related. The menthol patches like Salon Pas or Icy Hot. Arnica cream or gel onto the area. Icing it. Ibuprofen. Stretching is essential and remember that often where you hurt, it's a result of other things being tight. So, stretch out completely (but do so gently and try not to do a cold stretch, go for a walk and then stretch). If it goes on for a while, then yes, see your doctor.
Probably just need to stretch and move it around. is this the first time you've played in awhile? What position do you play? I'm guessing there was a lot of crouching you don't usually do that caused the problem.