I had an oopsie with an ex

So I made a mistake and slept with my ex who’s in a relationship. The last few weeks, I’ve been so anxious since then. I’ve felt completely off, and to make matters worst I was ovulating. Today I took a test, I think it’s negative but I’ve driven myself crazy verifying...I really would prefer not to carry his child and I wish I would have never done it. But no faint lines, right?