I agree with tclynx. Most laws regarding breastfeeding/pumping in the work place even for employees are not enforced. In other words, in most states there is no fine or reprimand for not complying. But they exist to empower and educate. MOthers still need to educate & convince their employers in many cases.
Here is a link from the FL breastfeeding coalition with lots of info for working moms. OK, you are a student. But I think you can use these ideas to help you talk to your school. http://www.flbreastfeeding.org/bfing_working.htm
Educate them about WHY pumping is vitally important for your health and your babies health.
Point out that your baby has had health issues, and that getting your breastmilk for longer is particularly important. If you have a sick baby, you might miss school or be distracted with worry.
Of course if you yourself are ill, you will miss school. Mastitis is a serious illness that includes fever and severe body aches, like the flu. No mom suffering from it is going to be able to stand for long, much less cut hair or learn. It can lead to mom being hospitalized. It is nothing to fool around with!
maybe think about what would help you pump at work. Have you identified a different place you could pump? Would your car work? Is there a way to make where you are currently pumping better? Be specific about what kind of breaks you need. Give a time frame (I will need to do this for ....months. That kind of thing.) Your supervisors probably have absolutely NO idea about the whys and hows of pumping and milk production, so even if they are motivated to help, they might not understand HOW to help, or feel they cannot say yes to your requests without more detail.
maybe talk to your baby's doctor or you OB about getting a note explaining why breastmilk is important for your babies health and pumping important for yours. Tell the doctor what you need IN the note.
Contact your local WIC. Even if you are not on WIC, they are supposed to help mothers with breastfeeding. They may have ideas for you. Breastfeeding help from WIC this varies county to county, with some offices doing a great job and others not so much. So ask around.
Contact local LLL. They should know what resources there are for breastfeeding/pumping moms locally.
Again, if you absolutely cannot pump more often at work, or cannot pump enough for baby to have while you are at work, (this can happen even when the pump situation is idea) then baby can possibly get more of your milk at night, and what you can pump can be given to baby. If supplements are needed, they are needed. The protective factors of breastmilk are not negated by having to give baby formula or solids.
Also be sure Grandma is feeding baby in a breastfeeding supportive way. Ideas: http://www.llli.org/docs/00000000000...astfedbaby.pdf and http://www.bing.com/videos/search?q=...FD00534CAAC56E