Certainly sounds promising, are the pains in your back also? Could they be pains relating to a stomach upset?
It does sound like prelabour to me, but yes, that can go on for a long time. Or it could be tomorrow It's all a good sign your body is preparing for labour.
I've had days of prelabour this pregnancy, period pain so bad I can't sleep at night and even periods of time where I have painful regular contractions, really bad nausea and bowel upsets. I'm expecting this to go on for a while yet for me due to what happened last pregnancy. So yep, definately not unheard of to have prelabour this early.

Keep us posted on how you go!