Hormonal imbalance or implantation!!

I’ve been on Tri Linyah for almost two years and it never made me spot, last

month about 2 weeks before my period I had brown discharge for about 3 days. Now this month I’m a week away from my withdrawal bleed and last night and today noticing small amounts of brown/pink discharge. I haven’t had sex, but my boyfriend and I have done foreplau like things? Someone help me