Hi.I think you have learned a $15.00 lesson already. I, of course, have done the same thing you are doing now.
And then the people on the board told me to do my homework and read more,which I am still doing.I can't tell you a whole lot about motors but you have to turn down the armature,add permanent magnets,maybe ,rewire the coils.if it's got bushings you have to add bearings..in your case, it may be best to buy a permanent magnet motor and start from there, maybe.Anyway, You are hooked now...no turning back! Good luck!