hours (rant kinda)

so ive been at my tjx for like almost 4 wks now. my hours have been SHIT, like im working 2-3 days with 4-5 hr shifts. is this like normal??? will it get better?? i also havent been trained for cash register (although i have a lot of experience with it), but a girl who came in a week before me with zero previous work experience and still in highschool is getting on the register every day for EIGHT HOURS A DAY. she also works SIX days a week. Im already putting in new jobs apps for other places, i rly like my management and some of my coworkers but this shit is stupid.