health issues

I started 6th form in september, doing biology, chemistry and physics. I have a genectic condition which causes pain , fatigue and also have dyslexia. Unfortunately I came down with glandular fever in October still not fully recovered. I did fine with my GCSES, even though I was off at times due to my health. I am getting really worried about 6th form but want to take A-levels. I am one of the younger students, birthday late July.