Is this normal at 35 weeks?

Im 35 + 5 today and the past 2-3 days i have been baddd lower back pain. Yesterday it was almost the entireeee day!

Last night it woke me up about 7 times i barley got any sleep. But also with the back pain i get mild cramping in my stomach?

Im not sure if it braxton hicks or not .

Everytime i went to the bathroom i did notice pieces of my mucus plug .

I also been having alot of soft bowel movements . Yesterday i went like 4 times and so far today i went 2 times

Could this be preterm labor?

I see my doctor at 2:45 today , but im a ftm and im worrying im going into labor