Yes it can happen that way, just cramps. That's how I went into labor with my first, I just felt cramps no tightening. Time them and try to walk around some, that should make them get stronger.
If the pain is down by your hips and/or above your belly button. That is ligament pains. It hurts a lot and i can't stand it. I somehow made it more painful by doing too much and now I can barely get up to pee.