34 weeks pregnant severe lower back pain and lower abdominal cramping! could this be labor?

I have a history of premature deliverys. I delivered both of my first two at exactly 36 weeks, and my second at 36 weeks and 4 days. I am pregnant wih my 4th child, and have been feeling "uneasy" all day. I took a bath to relax and started feeling some mild to moderate contractions, so i got out. since then I have been having severe back pain, abdominal camping, and "some" contractions. Should I go to the hospital?? My labor usually is mild then all at once ges super fast. So fast that I have never made it to the hospital in time for any pain meds. Please let me know what you all think that i should do.......