Lump on my palm. occasionally it hurts. about the size of a pea. what is it?

Lump on palm: This seems like a fibroma or a fibrous cyst or a scar on a tendon.

Calcification: there are several possibilities A calcification of a tendon sheath, ganglion cysts which is an injury of nerve and tendon in the hand, of a disease which calcifies the tendon in the hand especially the 4th tendon. If it grows or becomes tender see your provider