Dont feel bad im 15 and havent started puberty yet. My penis is only 3in long erect and cant ejaculate.
That penis size is totally normal, maybe even a bit above average for someone your age. Chances are yours has still got a little bit to grow, but 5-6 inches is average for an adult.
What you are seeing come out when you masturbate is pre-come. It happens when you are sexually excited, and when you have sex it can act as a lubricant. Guys don't always get this, it's more likely when you are most excited, and/or that excitement lasts a longer time.
Probably most boys can ejaculate by the time they are your age, but by no means all, so it is not unusual. Nothing to worry about yet, it will happen eventually.