WTF?? Weird light period!? TMI

I totally understand what you ladies are going through. DH and I are currently TTC #1 and it has proved more difficult than I thought. Hadn't had period since November and shows up today after 2 days of mild crampin and its super light? What is up with that? Also (TMI) had a small dark clot size of a kernel of corn on my tissue when wiping but other than that perfectly light and getting lighter has anyone ever had this before? Please share