welcome to healthcare magic forum
severe mono can affect your hair and you may feel hair lost up to 8-9 month after it.
we call it telogen effluvium
,it is due to stress
that body suffer during mono.
the good thing is that you will get your back in next 6-7 month
better to consult dermatologist
iron and biotin
based medicine will help you
eat more fruits and green veg ,do yoga and exercise
i hope i answered your question