Pregnancy questions

I am 14 weeks one day today and I’ve been experiencing a lot of abdominal pain and pain during sexual intercourse is this normal or should I be concerned and see a doctor? I’ve also gained 3 pounds already since being pregnant, is that a lot of extra weight in this time frame? This is technically my third pregnancy, first one I lost at 12 weeks and second I lost at 4 weeks, neither of them did I experience weight gain, I actually lost weight. I don’t want to be worrying over nothing but I really don’t want to loose this little peach, it would devastate myself and my fiancé.