I have horrible time management!?

i'm a college student ( i'm a commuter that lives about 40 mins away), im taking 16 credits the workload is in between moderate and copious, i play the role as second parent to my little sister at home, i work (every other day on average 12-16 hrs a week 5p-9p or 6-10),so on those day that i dont work, i have late cles and i normally dont get home until 7 or 8 pm. By that time im exhausted! , i have friends that live on campus , but i always neglect them because i just have so much stuff going on. If im not neglecting my friends, im neglecting my studying and/or housework. i just need help balancing everything ...it just seems like i dont get anything done---so frustrating...do you all have any suggestions?