If you eat a healthful diet -- don't eat bad stuff (trans/hydrogenated fats, sodas [diet or regular] ... cut out bread (even whole wheat) and sweets and starchy, high-glycemic carbs ... and eat all the whole, natural fruit and vegetables you can eat and some whole grains (and healthy fats from avocados, extra virgin olive oil and walnuts/almonds) ... then doing that and 30 minutes of exercise a day, even if just walking (or walking in place and light jumping on a mini-trampoline indoors, or cycling indoors) ... that will be enough so that you lose about 2 pounds a week. You won't ever feel hungry (cravings for sweets and junk food go away after 10 days or so), and you won't feel exhausted due to exercing a whole lot.
I've been doing that and have lost 60 pounds so far, averaging 2 lbs. a week. After that 1st 10 days/2 weeks (when the cravings for junky food stopped), it was easy.
You can do it. But eating healthfully is even more important than exercising. And getting 7-8 hours sleep a night helps a lot, too.
Don't stress so much about the 1 lb. weight loss. Go more by how your clothes fit and how you feel. Muscle weighs more than fat, so you may be gaining more muscle. Find the best time to exercise whether it's before work or after work. Get whatever time you can for a workout whether it's 20 minutes or 60 minutes. 20 minutes is better than 0 minutes. Watch your diet and your portion sizes to expedite your weight loss. Drink plenty of water.
I agree with Mary; I have stressed about not walking more than 30 minutes most days of the week. Then I realized that 30 minutes is better than no minutes and that I can probably build up to an hour after I have "conquered" the 1/2 hour without getting too tired. I also eat lots of veggies and fruits and watch my portions although I allow myself a small tub of ice cream once a week.