First of all, welcome! Everyone here is great. You'll get all of the advice and encouragement you could ever hope for!
Don't be discouraged! You've come so far...and everyone has fluctuations. The worst thing you can do is give up - just power through it. You really can do this.
If all you were eating was fruits and vegetables before...you definitely weren't eating enough (or the right things). Thandie is definitely the expert on this - but all I can say is you need to be eating protein. Fruits, veggies, and complex carbs are essential as well, but without protein, you're not going to build the muscle you want. And I used to HATE eating any form of protein...now I love it.
You mentioned that you feel so full - like you're stuffing your face. Eating whole foods makes me feel fuller than eating processed foods or simple carbs. I also ate just fruits and veggies at one point in my life (not balanced at all). Once I incorporated other complex carbs (oats, whole grains) and protein, I felt full SO quickly. Because I was so scared of gaining weight, I stopped eating when I felt full, therefore not eating all the food I should have. So I was getting less calories than I should have (sounds like you think you might have this problem...) and not meeting my goals. It's good that you're so in touch with your body (not eating bread, cheese, or other things that make you feel bad)...you're definitely on the right track!
I wish you the best of luck!!! You're already doing GREAT!