This story is from when I was around 15; I had been masturbating for quite awhile by this time, and usually did it at least once or twice a day without fail.
My family got a really good deal on a rental condo down in Florida and it was here that we spent our March Break. The drive down was about 24 hours long, and by about Georgia I was dying for a smoke. When we pulled over to the rest area I snuck away and had one. When I got back to the car my mother smelled the cigarette on me, and told me that I was in trouble but we would talk about it when we got home, as she didn't want to ruin the vacation.
The vacation was fun, but there was absolutely no opportunity to masturbate. The condo was very small and we had to share rooms. The bathroom wasn't even private; it just had one of those folding doors that wouldn't lock properly. I thought I was going to die of 'blue-balls' for those 10 days. Between all the girls in bikinis on the beach and being in close proximity to my mother and well-developing sister changing right in front of me, I thought I was going to explode.
For the whole drive home I couldn't sleep at all. I was so looking forward to firing off a few knuckle children in the privacy of my bedroom. When we pulled in the driveway I quickly got out of the car with the intention of heading right for my room, but as I was doing so my mother reminded me that we would be having that talk about smoking right away. I went inside and decided to delay my punishment for a little while by taking a quick shower. It was all I could to not to spray right there in the shower stall, but I thought, hell I waited this long I can wait until I finish getting shit on and then really enjoy it.
I finished my shower, wrapped a towel around myself and went to my room to get a fresh change of clothes. As I was walking through the kitchen I saw that my mother was on the phone. Bonus!! When my mom gets on the phone it always lasts at least an hour - now finally got time to finish myself off. I walked into my room, threw the towel my chair and hopped on top of my bed. Between the kitchen and my bedroom I had grown a raging hard on and slowly started working it thinking of all the girls I'd been ogling the whole vacation. I'd never felt my cock so hard before, and had never let myself go 10 days between jack off sessions before. I knew it wasn't going to take long, but I didn't care, it just felt so good to play with myself again. I felt myself on the verge of cumming and decided to cross that point of no return and cream all over my stomach. I was feeling the first wave of cum surging up my shaft when out of nowhere the door to my room flings open. It was my mother, off the phone early and down to talk about my smoking. I had already let myself go too far......I was cumming and my mother was watching it!! I spurted farther than I had ever thought possible. Five ropes of semen shot out of the end of my cock. I was trying to cover myself up, but in the process I ended with cum all over my hands, stomach and even face. My mother looked shocked; the only thing she could say was 'oh' and walked out of my room closing the door behind her. I had never been so embarrassed in my life. I was still laying there in shock and covered in my own man yoghurt, when I realized I should clean myself up. I got up off the bed in kind of a daze and got the towel over my chair and started wiping the cum off my face. As I was doing this my mother walked back in the room. I quickly wrapped the towel around myself. My mother asked me to sit next to the bed with her and talk about what just happened. I thought I was going to die. Then she shocked me. She said she knew that boys did that and she was sorry that she violated my privacy and caught me doing it. She went on to say that masturbation is healthy, and that she and my dad regularly do it, and I should feel free to do it whenever I felt like it. I really appreciated my mother saying this, because if she didn't I think it may have made me feel that masturbation was bad and looking back at all the fantastic masturbation sessions I've had over the years, I would have missed out on a lot.