If you think that, then you are. You can change this thought process by working on things that will improve yourself such as if you don't have a full time job, aim for one. If you need a college background or trading school experience, do at least one of these things. Volunteer at a convention and/or continue to go to events here and there.
When you improve your independence and knowledge of things around you, this will automatically make you more attractive and you will feel more empowered and happier.
You have a very youthful age, and heck, I think your appearance is attractive, but I don't believe you are into men on top of a mutual attraction, respect, and emotional care toward each other. So, there, you have at least one person you now know who thinks you are an attractive person!
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One time, I befriended a person in his mid 40s who had extreme wrinkles (mostly due to his weight and the way he stressed himself out) on the spectrum. Turned out he had an obsessive crush on me and when he understood I wasn't interested in him in that way, he got angry at me and had me kicked out of a social group for people on the spectrum all because he had a crush on me that didn't work out and nothing else. I had suggested he consider people who are like 60+ because a lot of them would probably be interested in him and his look tends to be more like theirs.
I was also too honest with him when he pushed me to tell him why I didn't want to him with him. I told him I thought he was ugly verbatim, nicely, but it hurt him.
If I could show you a picture of a truly unattractive person looks wise (and with personality, makes it worse) in most people's opinions probably, in private, I would. lol.
Also, if you are unattractive, you can always possibly improve your appearance and also keep in mind that "looks" are subjective too. So, some people might not like a certain race because they are that race. It is annoying, but don't let that hold you back. Try to use the scenario you are in to your advantage. If those people aren't attracted to you, maybe they'd be that much more trouble to be with and not worth your time and energy.