I'd agree - rest. After even a few days without playing it gets a little painful if you play too long. After a long time off, you need to build up gradually.

Work at it too hard and too masochistically and you might even get some kind of blister under the callus, and it'd slew off...

Play till it starts hurting enough to make it not fun playing any more, and then rest it. Maybe just one tune or somg. If it hurts too much even to do that, give up for the time being and try a different way. Toughening up the fingers with surgical spirit might be a good idea, or breaking them in with something a bit softer, like nylon strings.