Is it normal?

Is it normal to feel so nervous when planning to try for a baby? We haven't officially started "trying" yet, but just the thought of it has me thinking all sorts of crazy ideas & I'm fearing EVERYTHING! I guess this time around will be different since Grant was a complete suprise for us. I worry it will take a really long time, I will miscarry, or something will be wrong with the baby. I have alot of friends and family who have dealt with one or all three of these things and I just feel for them and admire their strength through all of it... I don't know how I would do it, but I guess if thats my future, I will embrace it & do my best. I also have this weird feeling I will be the one with twins. Nobody real close to me, family or friends, has them & I keep thinking maybe I'm the one! I would actually be excited for that, but it would also scare me SO bad too and again, I worry about my strength through the hard times like while they're newborns, busy toddlers, or bratty teenagers! This is a little off subject, but my first day of computer class the professor came around to individually introduced herself & to get to know each of us a little. I've never had a professor take that kind of time! Anyway, I had just picked an open seat and happened to be sitting between two girls who both just had twins! They both had no idea until 20 weeks & both didn't have it in their families and weren't on fertility medication. If you know me, you know I'm a weirdo who thinks it must be a sign that this will happen to me. I mean really how did I pick the seat between these two after already worrying about that myself?! I guess we'll just wait & see & what will be will be! I mostly just wanted to document this for when I am right & something unexpected happens next time!!