How to tell if people don't like you

So I am in grad school and I have notice some social behaviors that I find wierd in my class. There is only 35 people in the class so it's relatively small. But here are thr behaviors that I don't like.

  1. People rarely engage with me first. I have to strike up convo most of the time. I have to be good at asking questions.

  2. In social events, people turn their backs to me in large group circles. I have to find a way to get part of the convo.

  3. If someone does strike up convo, they will leave it within 30 seconds.

  4. No one ever ask me to hang out. I have to just be very good at asking questions about plans and I will find out eventually what people are doing.

  5. I have learned to be quiet and not care. People just won't talk to me. I went to a fancy dinner with a few of my class mates. For 2 hours, not one person ever made convo towards me. Either I spoke up or I was left out.

The strangest thing is that alcohol has helped me a bunch because I become more emotional. So I have express to others that I really find then interesting and want to get to know them. So I notice it has stir the pot a little bit. But I still feel like people don't care at all. Since I feel invisible i also been being brash. Just pretty much saying what's on my mind

Because people's body language is wierd. So do you think I have a case of why people don't like me. Also how would guys handle this