Worried about problems or Am I ok?.

How risky, with regards to getting infected with HIV or other STDs,
is rubbing the unprotected penis lengthwise in an up and down motion on the
buttock cheeks ( no penetration involved of any kind ) also the female sitting on me and rubbing on me with i wearing the underwear
and the female nothing ( last for 4 minutes)
How risky is this behavior from female to male transmission
because three days after this encounterafter i got flu ( body ache fever and cough ) i dont know whether it was because if that encounter
or because of my collegue who sits very close to me and cough all the time....

[H. Hunter Handsfield, M.D.]

Zero.  Those practices won't transmit STD.  Getting influenza (or a bad cold) 3 days later undoubtedly is just a coincidence.

Good luck--  HHH, MD