Second pregnancy!!! This one is so DIFFERENT!!!!

I'm 6 weeks and 3 days into my second pregnancy, and boy are things different!!! I didn't have hardly any symptoms with my first (she is now 2). Minus a little bit of moodiness, and with this baby, I have nausea all the time and so much gas... My boobs hurt, I go from being happy to grumpy to lovey to horny all in 10 minutes!!! I was 14 weeks when I found out about my first; and now I'm so afraid something is gonna happen and I'm gonna lose this one!! First child with my fiancé!! Anyone else feel the same!?!?!?!?