If you can feel your pulse on the "lump", its probably just an aneurysm. I had one from a baseball injury, and had surgury to repair it.
google "ganglion cyst"
I'm not a medical person, but have said a prayer.
I hope it turns out to be something minor.
Good luck!
Could be trigger finger.
http://orthoinfo.aaos.org/fact/thr_report.cfm?Thread_ID=168&topcategory=Hand
Wear a wrist splint at night.
Can take aleve every 12 hrs if tolerated.
I am NOT a doctor.
I hope and pray it turns out to be nothing. Don't apologize for being concerned about your help and seeking input from some very intelligent people!
ping
http://webmd.com/
Above URL lets you input symptoms and get some good info!
If it is a ganglion cyst, the way I used to treat those was to cleanse and numb the area, and then use a big honking needle to draw the gel out of the cyst, because it's too thick to come through a slender one.
Then I'd aseptically change the syringe to one with a touch of Celestone (a cortisone liquid) diluted in xylocaine and inject the cortisone into the deflated sac of the cyst to sooth the inflamation that caused the cyst and get it to stick together so it wouldn't refill.
That seemed to take care of practically all of them.
Don't pay for an expensive operation to remove the cyst unless this aspiration and injection treatment fails.
As a few others mentioned, it sounds like a ganglion cyst. They are harmless, and can spontaneously disappear, especially if it is smacked hard. It can be surgically removed if it's interfering with your activities of daily living. Be sure to see your doctor anyway -- the web is no place to get a definitive medical diagnosis.
Thank you all. Will keep you posted.