7 weeks 3 days HELP

so I am 7w 3d pregnant. i still have little cramps. I had a miscarriage in october when I was only 5w. my husband an I are so happy but also scared. how do you know if it's an ectopic pregnancy? How do we know if everything is ok?? It's still so good to be true, and we can't see anyone until 11weeks, April 6th. I'm also so scared because I drank alot of alcohol a week before 5w - I didn't know I was pregnant obviously. how can I ease my mind?