Second Time Around

My first miscarriage was in September of last year. After having a positive pregnancy test 3 days ago, I am now miscarrying this morning. It's a lot worse than I remember. The cramps have been so bad I feel like I am going to throw up. Luckily, I spent the night at my Mom's house last night so I have her here with me this morning. Something I don't remember from last time was passing out. I have passed out twice in the last hour already. My mom is a nurse and said that it was probably from pain and that I shouldn't be concerned. Has anyone else experienced symptoms like that before? I'm only 20 and very concerned about infertility.