Heavy vs. Broken

Last night I wanted to get a jump start on my new routine so I got on the treadmill to see how far I could walk in 30 minutes. But I wasn't able to go that far because every time I got on the treadmill, it would stop going! Was I too heavy for the machine or was the machine broken? I don't know either way, but because I am heavy, it's a good probability that I was just to heavy for that particular machine. But that's ok, I may be too big for the machine, but I'm not too big to walk on a track.