Eating help

Ok soo.
This hasnt been going on long well a few months I guess.
I'm a vegetarian and have been for a year and a few months, I dont eat fish neither
But I feel like I'm getting fat, people say how I'm stupid for thinking that and I dont need to lose...

weight.
I know lots of teenagers go through the stage of feeling like this
Ever since being a veggie I started getting stops like on my arms etc, and I'm starting to get quite a few on my face now too
Also when I have tea I cant even finish it because I feel like I'm full and need to be sick, I'm not trying to make myself sick, it just happens as I eat, very small portions do this too me.
I've lost abit of weight and my mums getting worried
I'm 14 and I'm quite tall, usually my trouser sizes would woman size 10, 12 or 14.
I put on a pair of shorts today size 13 in teen sizes and I could nearly do them up
had anybody had something like this? what's happening to me, and would it be a good idea to go to a doctor?
thanks :]

dude, you sound healthy, if you want to lose weight dont cut back on food, excersize

I have been excercising, I int trying to cut back on food, I eat and eat but I cant eat much so it's like I'm cutting back on food =/