Leaking breast milk

So one day my mom had to rush off to work and I had to finish washing my baby brother whose 5 months old and when I got him out of the tub we latched on to my breast because apparently he was hungry. But at the time I was wearing a tank top and no bra because I had just gotten up. So what happened was I pulled him off and I started uncontrollably leaking breast milk all over. I got him dressed and put him to sleep and for the next ten minutes I was trying to stop from leaking milk. When I finally got it to stop i changed my wet clothes and cleaned up. I thought everything was fine and that the baby had just somehow made my breasts start leaking. But the next day when I heard from crying for food my breasts started leaking again. Also another problem is that I heard how when ladies who had just had their babies leak milk when babies are crying but I've never had sex so its weird. Also women who breast feed have rapid breast growth and I think its happening to me because last week when the first incident happened I was a large C cup but now I'm a small D cup I don't know what to do about the leakage or the breast growth can someone please give me good advice on how to stop this without having to go to the doctor. thank you for helping.