repairing the sense of humor

i don't know why but i've just felt like laughing for no reason as of late. i started to laugh in the van ride home from swimming today. i don't know if it could possibly be part of my brain rehabilitating or repairing itself (which i hope anyway, so i don't feel as much like a nut). my voice lost it's "tone" in the car accident and i don't know if i lost part of my sense of humor.