Boy, your excuses (plus a few more) sound like the ones that I used for 30 years. My weight was the same as yours when I was about 22 and two years ago I was bumping up against 300 pounds. Because of those excuses, I kept putting on weight and I found myself in my fifties with worse knee and back pain, almost immobile with a lot of physical problems.
On the days that you are tempted to skip that exercise and eat that junk food, please think about your future. If you don't come to terms now with handling both your life and your weight, you could end up like I did. It is important to make time for yourself so that you can deal with everything that life throws at you.
Another thought........ many of us who are losing many pounds worry about our skin recovering. We talk about wishing we had thought about stretching our skin when we were gaining weight instead of waiting until we are losing it. When you are tempted to let those excuses win, think about having loose hanging skin.