is this enough excercise?

I was wondering if this is ok exercise for someone who wants to be active. I work at a job where I stand all day so most times I feel too tired to work out. I have been walking 2-3 miles 2 or 3 days a week. I have also been doing my own version of aerobics in front of the tv on the days when its too dark to go on the nature trail after work. I do it 20-30 minutes and it gets my heart going and I break a sweat. Its almost like doing light tae bo. Is this ok? I know I should do more but its hard to want to do something when you've been up since 5 in the morning.

It's enough if your meeting your weight loss goals, assuming that's your goal. If your goal is to simply be active then I'd say mission accomplished. Need more info.

I want to lose weight but I'm trying to find something that I will never have an excuse not to do and this seems to work for me. I've been watching what I eat and so far I've lost 10 pounds. I know half of it was water weight but the other half was fat b/c it hasnt come back. As long as I get my heart rate up its ok right?

It all depends on what you want to accomplish, what your goals are. If you just want to loose some weight walking and watching your calorie intake will most likely work. If you want to tone/build muscle  you will need to add strength training 3-4 days a week. HIIT (sprinting) will tone and build endurance and help you loose fat.