Am I in early Labor? (Please Read)

I woke up today feeling completely sore as if ran a marathon and did heavy weights. I am having sharp lower back cramping/pain and also menstrual like cramps. every now and then I’m getting mild but sharp shooting pain down my legs. Aside from that, I am just super nauseous and have the chills (no fever). I am also extremely tired. I have been feeling some mild contractions but they could very well be Braxton Hicks. That part could be confusing to me because during my previous pregnancy I was apparently having contractions and didn’t even know it because I didn’t feel them and the very few I did feel only felt like painless Braxton Hicks but the doctor reassured that i was definitely having real contractions. I am 37 weeks exactly today. I also spotted a tiny bit yesterday. the night before I was having mild contractions that only lasted 3 hours and were about 5 mins apart and then they completely stopped.