I'm 38 weeks tomorrow and have been losing my mucus plug slowly. I have the same pains you do and all that. I was checked Wednesday and was only dilated to a 1. If you feel nervous, you can always go in and get checked. But I don't think those things are a sign of labor. I've had this stuff happening for like two weeks now.
I have had some pain in the vagina and stiffness/tightness in my lower stomach. I think it is baby coming down and my cervix opening some, which I am happy for, I will be 39 weeks tomorrow and induced on tuesday.
But it could be your plug and cervix opening some, both of which can be like that for a couple weeks before you go into labor.
If the cramps get worse I would call your dr. Or go to l&d though.
I'd my first at 33weeks .... I'd b advise you to go get checked.
I have not experienced that but I would definatwly call your doctor or a nurses line to see what they say. Sinceb ur first baby was premature they may wanna take a look at u. Every pregnancy is different even when its the same person so this might be the start of labor for you.