38+4 constant back pain

HN
I've posted like four times tonight. Whoops. 😜 FTM, everything is new! 
 For the last few days I have had pretty good back pains (like crampy aches in my lower back). Came on Friday while shopping at Costco. Kicked back when we got home, it subsided, then lingered for the remainder of the day. Yesterday (Saturday) it was okay but I could feel it coming on after being on my feet and walking around. It's now 2AM (Sunday) and I'm laying in bed with these darn back aches but I don't think I've been contracting (and I feel my little girl moving around, so obviously not in labor). I lost my mucus plug around 6PM yesterday (brown tinged) then a few bits of (clear) mucus a few trips to the restroom after that. 
As of Friday, I was dilated 3 cm and 50% effaced. I guess I'm just posting to ease my mind and see if anybody has had a similar situation. I know she's coming early, it's clear to me that my body is preparing for her arrival. I am due in just over a week. 
Just hit me with your thoughts! Stories! Anything.Â