To be tired it is only in your mind.
If you don't like don't do it. But don't forget that: NO PAIN NO GAIN.
To be a good bodybuilder you must be a good observer.
Use what you have in your gym. Try to do my training program, you will lose your fat and gain muscles at the same time.
I do for one full hour non-stop of 2,000 sit ups and then 6 sets of leg rise.
Perfect form is the most important thing to have a perfect body, it's impossible to make a painting with a big brush