Too old?

Is 30 years old too old to go back to college? I took a few semesters when I was 19-20 but never finished a degree. I've only ever been a waitress and I don't want to be a waitress for the rest of my life 😫 I was going to go back to school for phlebotomy/EKG technician certificate. It doesn't take too long or cost too much. I figured it could at least give me some career options rather than just being a waitress forever. Thoughts? Opinions? Am I too old? I'm nervous all the younger kids there will make fun of me for being 30 and in college.