Kel, 2 things:
1. You won't want to hear this but you can indeed get AF when you're on the meds. I had AF turn up early after my first IVF even though I was on progesterone.
2. You will want to hear this one - I had pink light bleeding at 14dpo in our successful IVF and brown light bleeding at 15dpo. I was sure it was the start of AF, so you could have knocked me down with a feather when the b/t at 16dpo was BFP!
That said, with the other signs disappearing, you might be right, but it's never over until the witch sings...