Confused ?? i really need help please?

Hi. I am 18 years old. My period was on the 5th Nov-9th Nov. So between the 16-21 Nov was my fertile time. I took a ovulation calculator and it said I ovulated on the 19th and on the 19-21 of Nov. I was ually active with my bf. On the 19th we had and he said he thinks he d in me. He said it felt asif he did. But no *** leaked out of me. So on monday the 22 november I started having cramps like period cramps without any period. My lower back began to hurt but only a few times. So it has been 7dpo and in those 7 days I have been experincing tenderness( last night it was killing me) a lot of mucus discharge ( it feels like my period is comming out but when I go look its mucus ) I use the toilet a lot to urinate for the littleist amount of water or juice that I drank. And I have been felling a little more tires than usual. I stil experince the cramps. I should get my period the 2december so I don't know if it is pms or period or implantation or pregnancy. I have heard that pregnancy symptoms can't start that soon or is it just a myth ?? Thanks in advance for the advice