FTM and contractions/on and off

I've had cramping most of the night, woke up with lots of lower back pain and some cramping, thought maybe I just had gas and had to go bathroom. After I did cramping came back bad while I was standing, thought maybe I just need to sit down. Cramping still coming so I timed the contractions for 30 mins the were coming regularly under 3 mins lasting 1.5 mins app said to go to hospital.

Well I haven't cause they slowly went away. My lower back is still hurting and I can't really move without feeling pain in my pelvic area especially while standing. I know baby is sitting SUPER low my doctor felt his head the other day. Curious if I'm just feeling pains from pressure of baby or are these real contractions happening getting me ready....

Q's is can this just go away and then pick back up again in a few hours or even a day or two? 40 weeks this Friday.