Im 38 weeks and 1 day today with #2?

I started walking for an hour every night last thursday and last night after my walk i started feeling crampy, i woke up this morning at 5am to a painfull contraction, and have felt weird all day, my back has been bothering me and iv had period like cramps all day, i started having contraction about 2 hours ago but they are not regular but they hurt and my whole stomach gets hard and i feel them in my back. what do you think it is, early labor? or BH contractions, my baby started moving more when the contractions started ,and i havent hardly felt him all day till 2 hours ago