What happens if i call out sick during the 90 day probational period?

I work per diem and every other weekend at a hospital. not as a nurse, but as a patient safety attendant who makes sure the patient doesn't fall for those who are at high risk. i'm under the 90 day probational period because it;s been only 2 months. i'm really sick and i'm supposed to work this weekend. i really don't want to look bad, but i also do not feel well. i'm not sure what to do. is it okay if i call out sick and work the next weekend? i need to call the staffing office soon. and i was about to email my boss and let her know although i want to go in, i dont want the patients to catch anything either. i'm just worried since im in the 90 day period. i have a fever, nasal congestion, cough, and my body aches.