Worried ftm

Ftm and my doctor has me a little worried. Every time I go in and get my weight done he says I'm gaining to much somewhere and somehow but all my levels are normal and when he measures my belly he says it's on track. When I found out I was pregnant in Jan I was 130lbs now at 8 months (34weeks) I'm at about 160. Am I doing something wrong? I don't over eat and I eat alot of fruits and veggies.