after turning veggie i lost a lot of weight but my belly got bigger? why?!

Maybe your bloated? If you are not used to eating so much fruit and veg this can happen! Your body will get used to it soon enough and it should go down. I cant think why else your stomach would be bigger.

Honestly, you probably got what some call "skinny-fat". You can lose weight, but often times if not done right you are losing fat AND muscle. Muscle needs protein to maintain/grow, and if you are on a vegetarian diet you might not be getting enough.

Personal opinion: I can see the benefits of eating vegetarian, but meat is what will get you the protein you need. If you aren't eating vegetarian for 'personal' beliefs type reasons, I suggest eating tons of vegetable, and then some meat. Skip junk foods and and any bad carbs and you might be on your way to where you want to be!

Do a Google search on the 'Paleo Diet'... or a Yahoo search, I suppose, since we're here.