Feeling fat fast.. Help!

Krystie
I only just recently found out I'm pregnant and I'm over the moon! I'm only 5weeks 3days and I feel like I'm showing already.. I have new strech marks on both my sides ? haven't changed my eating habits which are pretty good.. I also get sorest lower back at night and can't get any sleep... Is it normal to feel this so early in? Should I go annoy my doc? He said everything's looking good with blood teat results and first scan will be 10 weeks..... That's was last week...  Any advice would be nice! Haven't told many people so can't really ask any family or friends. Thanks ladies :)