clear discharge a week after period but im on birth control?

My period ended 8 days ago and now I'm getting clear eggwhite discharge but I'm on birth control, I havent had this type of discharge since I started birth control years ago and if I'm not mistaken this means im fertile right now? I've been getting it since yesterday and the night before I started getting it my boyfriend came inside me (but this discharge is definitely not semen). I took an opk and it came back almost positive but not quite, I'm not sure if I already ovulated and my levels are going back down or if I'm about to ovulate and they're going up. Ill keep testing to try to figure that out. I just changed my birth control to this pill 3 months ago and its a low dose pill. I've never missed a pill, I always take them at exactly 7pm so im not sure whats going on, maybe the dose is just too low for my body? Should I be worried that he came in me?