First of all , what you do is totally up to you and not your friends , (yes they can advise you but nobody can tell you what option to take , we have free minds - unless of course there is pressure but it is still your choice to give in to it). Your friends may be only trying to help , but you are the one making the decision so only you will know if it is right or not. You can get married and all can go well , or you can get married and everything goes wrong... Either way there has to be a consequence , good or bad , if you don't you'll never know what you could've had and if you do you might regret making that choice so soon.
If you are unsure whether getting married is the right decision for you then perhaps it's best not to decide to get married if you are s unsure. You can/should only think about marriage when you are 100% certain what you are getting yourself into, marriage does not guarantee success and happiness , (neither does it mean its the end of the world) but it is a huge responisibility and not just a status update! If you want to get married because of the idea of being married appeals to you or you think you are of age to get married then stop right there... You should get married when you have found someone worth marrying , when you have found someone you want to spend the rest of your life with. So if you don't have someone right now then halt this marriage business and start looking for someone before making any further decisions.
Secondly your friends 'think' you have a personality disorder? So just because we sometimes act a little crazy and weird , (or maybe spontabneous) makes us have a disorder? So just because some of us are different and may act in a manner that might not be appropriate to others makes us have a disorder? Hmmm...your friends need to re-evaluate their judgement. If you think you have a problem then you do , if you don't think you have a problem then you don't! Simple really...and if it bothers you , I'd suggest going to a trained clinician to see whether there really is a problem or not but I would suggest right now not to worry about it because the more you focus on it the more you will believe there is a problem. And remember that clincians and Psychologists are only humans and even they can never be sure whether there ever is a underlying disorder with a certain individual , they only base their conclusions and judgements on what you tell them , and what you display to them. They are not God , they cannot diagnose you for definite , they can diagnose you and tell you that there may be a problem but that doesn't mean you have. Just like , if a doctor tells you that you have depression after you tell him your past ordeal , does not mean you have to have depression , it could just mean you had a bad day or were over-analysing things because you thought you needed a answer when really all you needed was to slow down and relax.
Only you can answer your own question, are you ready? Do you feel ready? Have you found someone? Think about the positives and negatives about this huge responsibility , don't make the decision difficult , get into reality , is this moment here?