Hi there! I'm also quite a shy and quiet person... whenever I say something in class, people do pay more attention than if it were someone else speaking, I'm guessing because I speak so rarely that when I do it's kind of surprising. However, I've never noticed people exchanging looks, but I can imagine how that must feel...
I used to be extremely insecure and self-conscious as well as shy and quiet, and back then people always identified me as the "quiet girl". I remember how frustrating and belittling it was to be reduced to that, and I've found that since I've gained a little confidence in expressing who I am, people don't see me as just the quiet girl.
I think that first of all you should remind yourself that being quiet and shy does NOT make you a "loser"! It's likely that your classmates do that "look" because they feel your discomfort, or, yes, because they think you're awkward. But at the end of the day, does it matter that you're awkward? I know that I'm an awkward person... for instance, after going grocery shopping or ordering food or pretty much any interaction with a stranger, my friends will point out how awkward I was and we'll laugh about it... and that awkwardness barely bothers me anymore, because I know it' just how I am and I can laugh and be open about it with others. So, maybe try to embrace your awkwardness, in a sense?
Other than that, the only advice I can give is to practise speaking more in class, giving your input more, voicing your opinions when the chance arises, and in the meantime do your best to ignore your classmates.
I really hope things get better! Feel free to
PM me, I'd be glad to speak about this subject more with you
