It would be useful to have a little more info here to give a more helpful reply.
What is your reason for running, what is your age, and are you planning to race?
What is a long run really depends on the distance you are training to run. If you are training for a 5k, a 5 mile run may be considered a long run. If you are training for a marathon anything between about 13-20 miles would be considered a long run.
As to whether 30 minutes to an hour is over doing it. It again depends on your fitness level/age and goal?
If you are just doing it for fitness and you are enjoying it, I would say what you are doing is fine, unless you are really young. If you are looking to get faster, it maybe worth adding some interval training. Happy to answer further if you can provide more info.