Sounds like tendinitis. There's A LOT on this board about this injury but here are the basics:
- Massage: Go get a very hard, very painful sports massage.
- Ibuprofen: 800mg 4X/day for 5 days. STOP after five days.
- High-volume Chins: 30 sets of 2 reps w/ 1-2 min rest done once every 5 days for 3 weeks. If possible work your way to 15x3 and 15x2.
I'm dealing with this problem too at the moment and I can tell you that the massage has been a tremendous help.
Obviously, I'm just some legendary dude on the internet. This is purely for entertainment and not medical advice. You should consult your doctor before doing any of this stuff, blah blah blah.