Hi, I Was Wondering If It's Normal Or If It

Hi, I was wondering if it's normal or if it happens to others, but I never want to leave my house. I always cancel plans with friends and cancel all events that involve going out. It's been like that for about 3 years but now it's getting worse. I don't even want to go to school anymore and I used to love it; the thought of it actually scares me. I hate the thought of having to face everyone. I have friends and I get along with everyone as I have never caused trouble and hate getting into fights. But lately I don't even want to see my friends. The thought of having to talk to them and have them possibly judge me (not necessarily in a bad way) is too much. I always to my homework and hand in assignments on time so I guess it's not the school work that I dread... It's just going out? I'm 17 and have never been diagnosed with depression but have been diagnosed with bulimia 3 years ago and social anxiety 2 years ago. I don't currently see a therapist.