Pregnancy symptoms, am I freaking out?

Lou

I've had my period 2 weeks ago and my fertile week last week, when I ovulated. I've had protective sex several times since my period ended, but for the past 3 days I've been felling a lot of nausea and man, did I just attack the fridge. I've heard it's a common pregnancy symptom that could come from 3 days after conception till a month after conception. Am I freaking out for no reason?