Otherwise, maybe its Braxton Hicks.... Mine were the same way. I was told that we will get more lower abdomen pain from a growing uterus so it could all be part of it. I am 28w5d and having some of these same issues.
That sounds like something you might want to call labor and delivery about. It could end up being nothing, but it kind of sounds like preterm labor to me. Better to be safe than sorry. Good luck. Keep me posted.