me and my partner(we are not together) kissed and cuddled each other naked for first time and we had some foreplay(nothing related to oral sex). the next day he developed severe body pain,headache,cold,fever,shiver & throat pain. in one day they went after medication and only cold persists. the very next day i had all the above symptoms and after taking pills am left now only with the cold. what would be the reason? anything serious?