What size pots are you using and how frequently do you water?
It sounds like they are suffering slightly from overwatering. Maybe wait a little longer before watering them. If your plants are getting a little droopy and lifeless looking after not being watered for awhile it generally means they need water. In your case though, the plants are drooping after watering, meaning the roots are probably being drown in the moisture and your plant isn't getting enough oxygen. If your plants are bouncing back and not showing any discoloration it probably isn't a big deal, but if they show some yellowing or browning at the edges of leaves along with drooping then you are probably over watering. I would give it an extra day between your next watering and see what happens..