is this slow labour or BH?

Hello ladies im 39 +3 weeks & a FTM so have no experience in what to expect so hopefully you can help? Sorry this is gonna be a long one..

Yesterday morning at around 5 I woke up with lower back pain coming amd going. They felt a little stronger than the bh ive had before, the pain went round to my stomach and felt like strong period pain. These lasted about 4 hours coming every 6-8 minutes. Then for the rest of the day I just had the odd contraction and a constant dull ache in my back and stomach. 

Then at around tea time last night I got constant contractions again lasting around a minute every 5-7 minutes. They were getting stronger and some of them stopped me from what I was doing. I  had a bath, and they seemed to get stronger. I tthought yes something was finally happening!  I bounced on my ball and then thought id try and get some sleep. I managed to get a few hours before waking up with pains again however they were not as strong as they were before. I woje up again around 5 this morning to go to the toilet and I got a shooting pain across my stomach, I had a few more contractions and then nothing,  since then ive had the odd dull ache contraction and constant dull period ache/back ache. 

Im gutted I really thought I was heading in the right direction last night, but as I havent actually stopped having pains im wondering if it is slow labour or is my body just being cruel? 

I had a mw appintment last week and she said baby was fully engaged but back to back. Everytime I get a contraction I feel alot of pressure  inbetween my legs and cramp like pain down my legs. Can anyone help please? ?

Thanks in advance