How bad does it look when you quit a job without notice?

I am currently an LPN and quit my job without giving my 2 weeks notice. I worked for a home health agency that you couldn't rely on getting paid on time most of the time. When I was hired they gave me a certain area of clients to make visits to. My supervisor pulled them away from me and gave the clients to another employee. They expected me to travel an hour away from home and I explained it before that I couldn't do it because I was getting no mileage and was only getting paid per visit not per hour. My supervisor was fine with it at first and said she would keep me at my same schedule because they was my clients. Well 4 weeks later she switch my schedule. She became upset with me and hollering because I said I could not do that schedule. Anyways, she said she would make sure I wouldn't find another job. I have quit one other time at a nursing home because afraid of putting my nursing license at risk so I quit without notice. I just graduated last year and want to apply for other jobs but afraid I won't get hired because of the situation. How should I handle this with searching for another job? The way I feel that I should switch careers because I feel like I don't even have a chance.