is insanity hard to stick with

Im on day 5 and im dreading the next workout! its extremly hard i dont keep up 100% in the videos but i make sure i keep moving and finish the video to the end and never give up. I almost gave up because i thought i wasnt fit enough for thid program, but i kept looking at all the sucess storys of people who were heavyer them me and older then me and figured out that i can do it. Its not gonna be easy but you got to make the 100% commitement!!!