Is it normal that i am 19 and haven't had a single relationship?

I don't know you, so I can't say why you've never had a girlfriend. However, your situation isn't as uncommon as you think. I know some great guys in your situation, and some great girls as well.

I'm not an expert on this, but I've got some advice for you. Don't think you can't get any girls. If you think women don't like you, you'll come off as insecure and that's not attractive. It's a self-fulfilling prophecy.

Dating advice aside, it's great that you have a lot of friends, and that you have a lot of fun. Keep that up. If you lead a happy life, there'll be plenty of girls who want to be a part of it. :)

Dont stress about it. That will doom you. Accept yourself and take care of your business. Thats what life is about, not women. Thats step 1.
When a woman in whom you're interested comes around, be assertive from the get-go. Dont wait for her to introduce herself to you or make a conversation interesting or ask for a second date. Relate to her and respect her as a person, but if you want it, take responsibility for making it happen. And if you follow step 1 and take care of business before worrying about girls, she'll see it, and know that you're ambitious and don't NEED her. Even if you WANT her, and are willing to do what it takes to get her. That personality trait matters much more than looks.
Then, as the relationship progresses, assert your agenda. Whether it be a committed relationship or sex, again, make it clear that you want it. Then the ball is in her court, because its not like you can make her do anything. At that point, you win or lose and move on.

I wish I could say that someday you'll meet someone who'll care about you. I wish I could say that looks don't matter. I wish I could say these things, but I'm slowly starting to have my doubts. All I can say is that you're not the only one who feels this way.

I'm a girl in a simmilar situation... Actually just posted something simmilar... I don't know what to tell you other than you are not alone :)

It's normal! Don't worry :)
I didn't have a boyfriend until I was 21. Honestly though, I was really smart and studious and didn't really make a lot of room in my life for boys or friends in general. However, after I finished University, I shifted my focus and found my husband with ease.
My mom always used to say that you should work on finding yourself before you find your mate. It's actually good advice--it makes you less clingy/needy because you're already comfortable with being alone!

I wouldn't go so far as to say "normal" but it's definitely not uncommon. I was 18 before I got my first gf. Mostly because I was an awkward person, though. But if you're trying to get one it might be your approach that's hurting you.

You haven't mentioned asking anyone out. This could be the problem. You need to just ask some girls that you are into out then eventually one of them will say yes. Don't just go around and start asking girls out at random this will make you seem desperate. You need to almost strategically ask them to places. One way to get your foot in the door is to find a social couplesish thing, similar to a dance. And ask one of the girls that hasn't got a date yet. Then on the date give the girl complements. This has worked for me multiple times.

You will. Just be patient.