I feel that i am out of will-power. It seems impossible for me to really put myself seriously into something.

It's not unusual when we feel that everything is like a big wall that we have to overcome, despite the fact that we can't even get out of bed.

The simplest reason of our weakness would be the fact that we are really tired this period and we need rest or vacations.

Second comes bad nutrition and/or bad habits in our lifestyle. Healthier choices and more energetic life would do the work.

Third and most complicated comes some kind of depression. If it lasts more than a week or two, we need to get serious and discuss it with a very trustful person like our parents/family/older friends. If this doesn't help, we need to seek professional assistance in out school/work/hospital.