Had an X-ray a few DPO and now I'm pregnant - freaking out

Me and my husband has been TTC since end of 2012. Because of French regulations for my visa I had to get a chest X-ray two days after my calculated ovulation date. I thought the chances of being pregnant were nil but I did tell the technician that if I was pregnant it was less than a week. She asked if I missed my period and I said no and they went ahead. 
Now after all this time I had a positive pregnancy test this morning 17 DPO
Terribbly worried I mutated my baby.