just need some advice

I had my son 3 weeks ago. He was a true blessing. Me and my fiancé had been trying for 4 years, to get pregnant. My pregnancy was a bit rough. My fiancé lost his dad in January of this year; and we found out in March. 
Well, I had my son via c-section 11-3-16. He's absolutely perfect and I'm so in love. But now I'm not sleeping much at all. I'm terrified of SIDS and of course reading articles probably isn't the best. But I'm afraid of losing him and I stay awake watching him and Listening. Making sure he's breathing. 
I'm not sure how to get any kind of sleep. 
I am back on my medication. Which helps some. 
Am I the only one who is like this?