Weight gain

I feel like I'm struggling to put on weight. I am overweight by about 30 lbs. However, at 17 weeks I'm starting to be concerned. I lost about 5 lbs in the first trimester and haven't been able to fully put it back on. I'm hungry all the time but I'm not able to eat much without feeling sick. I would also say I'm eating healthier. It's much easier for me to keep down an apple verses a piece of cake. Have you experienced this? Suggestions? Should I be worried?