Whats the #1 thing that can't happen during cycle?

Getting the flu... Didn't feel like myself monday and after helping with a class and then taking the adult class on monday I wasn't feel 100%. Went to publix and started to decline fast (had to leave with only 1/3 of my shopping done). Got home and passed out. Woke up at 11 pm to a 102.5 degree temperature... I will say this, Tamiflu is amazing!!! Got a script for it yesterday and took my 2 doses, with a 3rd dose this morning (and 4th will be tonight). Fever broke and am down to 98.6 today and feeling much better. To bad I got 0 requirement in for yesterday and today (not going to push myself just going to sleep some more and hope it is alll over).