I have this pain on my lower left hip area... What wrong?

I would continue on your current course of treatment, but if you see no improvement in about five days, you should see a doctor. I doubt that you have a major injury since you were not hit with a blunt or sharp object. I wish you well. The possibility of a blood clot is not probable since you do not have a bruise. But do be careful and don't do anything to further injure yourself and take it easy not to strain your leg or hip. Good luck with your recuperation!