You sound similar to me. I am sooo healthy and then I get pregnant and eat rubbish (along with healthy...I just EAT). Anyway with DD2 I put on 10 kilos in first 16 weeks, and low and behold the exact same thing this time!! My OB said it's fine as he thinks Im underweight normally, but I will say, just enjoy. With both my pregnancies so far, once I had bub I was back to my pre preg weight within 3 weeks (bizarre since I put on 15kilos in the pregnancy)> That's another thing, my weight gain slowed down from about 20 weeks. So most of my weight was early on.
But I am finding with all three pregnancies, Im putting on the same amount of weight (ALOT). I too really don't like it, Im very self conscious and to be honest I feel like covering up all the time and not being in public alot. Most people Im sure would say I look fine, but I HATE feeling like this. The only light at the end of the tunnel (and this excludes my beautiful bub, I am talking purely weight wise) is that I know I'll lose it. Doesn't matter how long it takes, once bub is born you can concentrate on it then. xoxoxo