TTC, I don't know if my period came on a week early or if its implantation.

Hi, me and my DH had intercourse the week I was projected to ovulate. Exactly a week later, I began spotting, its not light but then its not heavy and its been on for 5 days now. I usually get cramps during my menstrual but i didn't get any just funny twinge feelings throughout the past couple days, and I was gagging on food that i rather enjoyed the other day. What are your thoughts? This all occurred the week after ovulation and a week before my projected period is supposed to come on.