Pregnant with my ex boyfriend's baby?

So, we split up about 4 months ago now. It was my fault and I did push the guy to breaking point. We never spoke or even looked at each other until just a few weeks back. We have even started talking and flirting a little again.

Anyway, past few months my period hadn't came (sometimes it doesn't come due to the contraceptive shot I get) so I thought nothing of it. Although I had been feeling nauseous and a bit hormonal recently.

Lately, I've been sporting a very small bump... and had a little bit of morning sickness. So I decided to take a test to be safe. Sure enough, it tells me I'm pregnant. Roughly 15-16 weeks.

My ex was all about having kids with me when we were together and he did really want me to be the mother of his kids. I'm not sure how he'll react when I tell him and I'm absolutely terrified at the thought of having this baby. What should I do?
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Please answer away guys/girls! Time really is of the essence here and I kinda want to tell him before my belly ends up doing that for me :/
Pregnant with my ex boyfriend's baby?
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