Help confused!

Larah • Almost 19, 1 miscarriage. Have severe endometriosis. TTC very much want our first bubba.
Did anyone before implantation or find out they were pregnant get cramping and back pain like they were bout to go on there period? My only concern is I'm meant to be in my ovulation week peak is meant to be Monday . But I've just tonight got sore boobs and cramping and sore back :/ never had this before can you conceive this early and so quickly?