Period-Like Cramps at 37 Weeks

Friday was my last day at work before maternity leave and I felt off all day. For some reason I just had this feeling that my baby was coming soon. At the time I was 36w6d and had been losing small chunks of mucus plug for 4 days in a row.

Then Friday night, when I went to go to bed, I had terrible pain in my right hip that shot down my leg and I got just 3 hours of sleep before waking up to terrible pain shooting across my pelvis. I thought for sure I was having a contraction but eventually it went away and didn't come back.

Saturday I had mild cramping but no consistency whatsoever.

Today though (Sunday-37w1d) I've been having almost constant period-like cramping. Over the past hour it has come and go every couple of minutes but I feel like if it was contractions the pain would be more intense...I did walk about 1.5 miles this morning and was 1cm dilated and 60%effaced at my appointment last week...could this pain just be more dilation?

I have a doctor's appointment tomorrow morning so I'm just trying to wait it out unless the pain gets a lot more intense but has anyone ever experienced anything like this?