Please help me :(

So I think I just got AF.. I am terribly upset. Cannot stop crying. But unsure if it's implantation bleeding?? I have missed my period by 7 days, it is NEVER late. If it's not on time then it is early. I have so many symptoms. Sore tender heavy boobs, constant headaches, increased appetite, dizziness (which I have never felt in my life), been so tired, nauseous, stomach pain, (I never get ANY symptoms when I'm getting AF) I am so confused. I had 2 positive hpt with faint lines, I just took the tests yesterday. Feeling so confused and upset :( what does implantation bleeding look or feel like?? Could somebody who has had this and been pregnant tell me their experience?? Would me the world to me. The weird thing is is that this has happened at 8pm, I ALWAYS get my AF in the mornings and it is heavy. Also I haven't been stressed or sick or anything so I can't understand why my period would be late. I just feel absolutely shattered and torn but am hoping it's just implantion bleeding.