Please help! school problems

So I've been missing from school 4 days now, each day my mother called into the attendance line to let them know I won't be there because I am sick. I've been gone a total of 11 days so far and it's only 1 month into school. I first had trouble with my gallbladder, where I developed stones. They took an ultrasound to see if the stones were stuck, but my bile duct was enlarged meaning that they passed. After my gallbladder incident, I started getting really sick (I haven't received flu shots yet because it's too early my mom thinks) so it might be the flu. I have been throwing up for 4 days now and that's why I am gone. Today I got a call from the school and I was sleeping when they called so I only saw the caller ID and it was too late. They didn't leave a message but I'm scared they'll fail me or hold me back for being absent so much. It's not my fault that I am vomiting, I just don't know what to do. I've been getting my homework picked up for me so I'm not falling behind, it's just that I lack turning it in because I'm sick. What do I do? (I'm in 8th)