Is it contractions?

I'm 28+3 with twins, I'm very small, and my doctor told me I wouldn't make it even close to my due date. I was in the hospital once at 25 weeks because I was having contractions, but not dilated and they stopped. Now for the past 4 days I've been very crampy. Yesterday and this morning are probably the worst. It's on both sides on my stomach by my bladder and also my back.