beginning pregnancy worries

Today we found out after a month and a half of trying that we are pregnant. I'm about 4 weeks along. Two pregnancy tests days apart and a missed period confirmed it.  While I want to be excited all I feel is worry. I'm terrified that it was too "easy" for us to get pregnant and that I'll end up having a miscarriage. Anyone else felt like this? This is my first pregnancy and the Internet has only made my worry worse. Any suggestions on how to stop worrying and just enjoy it?