Why is my top speed 70 mph?

This is probably going to be one of the silliest things to ask (you should expect a few silly questions from me, FYI) but I had problems getting it started today (again, a wiring issue I am trying to find) and so I pushed it a couple of feet and found that the rear wheel was squeaking as I pushed it and it was difficult to push even with a slight decline. It made the same sound that it makes if the E-brake is on. I got underneath and there is no E-brake cable even, so I fiddled with the outside of the drum and there is something wonky going on with the E-brake cable coming out of the drum (it is very loose and makes a lot of noise inside the drum). It was getting dark, and it started raining, so I did not dissect the rear drum brakes to see if I had an E-brake rusted and stuck on. It does not push easily, and it does not roll as easily. I am wondering if this is the problem. I do not smell burnt brakes when I drive it, but I will check into it and see if there is just some pressure on the brakes. And yes, I did have it in neutral. I certainly appreciate all of your suggestions. Be patient with me as I do not have an inside place to work on this, and I live in WA state, where it will be raining from now until July. We are also expecting a cold snap, so I am not sure when I will be able to dig into this. Hopefully tomorrow, but maybe not. Oh yeah, and I have this thing called a job that keeps me from my cars. ;)