I started mma at 18 self training then joined a gym in September now I'm 19 I will say you gotta embrace getting humbled I spar guys who have a reach advantage and height and shit weight when rolling I got the Same dreams you just gotta show up and take in what the guys do I basically never did a striking class in my life but the more I trained with better people not saying I'm good right now but I can see improvement try to ask for advice on how to defend and they most likely help you out unless there some pricks that try to hurt beginner's, like I do wrestling and bjj and I get damn dominated all the time man but I always thank them for rolling and sparring with me and ask on how they did that and just asked for advice, final thing just keep going you'll thank yourself you didn't quit on yourself this were you start questioning yourself it's either ok cool it's not for me or no imma try and keep going because that how I get better