Hi there,
Just to be safe, check all her teats, and make sure there is no sign of infection(redness, heat, swelling). If there is an infection, it would have to be treated, with the help of your vet.
Make sure she's getting some extra calories. My pregnant and nursing moms always liked yogurt...
Hopefully, like Debbie said, she may just need a nice run every night to get away from the kits.
Lori