Fletchersketche

Hello. I am new to this site and need help! I got myself a second hand 2005 dt 125, yesterday, I was riding home and it ran like new, when i stopped at home and got back on it it ran okay for a bout a mile and a half and then it stopped the engine would not rev, and it continued to slow until the engine stopped, it would not start again. So I waited a couple of minutes pulled open the cluth, and it started,, it ran for another mile or so and repeated the same thing, it wouldn't start, luckly I was close to my destination and was able to walk back, however, the battery was being drained from trying to start it with the electric start, and died on me this morning where I had to push it for 5 miles to get back home.m I am charging it up as I speak but I would like to know if anyone else has experianced this porblem or anything similar and if so..how do I stop it?!?! Thank you. Fletchersketche