Thanks for your question. It could be a flu
, but in this case, it shall be unlikely. I suggest to go to the hospital for blood tests to be run. Progressive ascending body weakness in face of an infectious syndrome is classical with a clinical syndrome called the Guillain Bare Syndrome.
I would suggest you visit your neurologist
for an appropriate work up.
Blood tests that shall be run would exclude other bacterial infections and autoimmune conditions that could present in a similar manner.
Consulting a neurologist/internist as soon as possible to be on the safe side is a reasonable idea.
Hope this helps and best regards,