I am 28 weeks pregnant and I am very emotional stressed out to where I cry about everything and I am very tired exhausted because I am in college and I am having problems with my baby daddy so can stress cause me to go in preterm labor

There is some thought that excessive stress may be an issue, for some women... but certainly plenty of women have a good deal of stress, some most of us will never be able to imagine, and they still carry full term.
Usual types of stress are unlikely to be of concern other than to make you more uncomfortable. Do what you can to take control of the situations in your life that are causing you stress. Stay on top of your school work if that is an issue, take fewer classes next semester if that is an issue, become better organized with your time, etc..
Have a talk with your baby's father and try to sort out what issues you are having with him. If you can't right now, might have to let him know that things are too stressful for you right now, and you will have to back off a bit.
Be sure you are taking care of yourself... make some time just to relax and do something you enjoy, go out with friends or family, nap when you can, make sure you are eating well, etc..