hi am 24 years old ! just over the past 7 months i have been seeing my partner who i am very in love with, both of us are very sexually active, sometimes we have sex more then once a day! today in the shower i noticed a little sack of blood on the tip of my penis! do i have a STD!? it does not hart i tried bursting it and just made it bigger what do i do! will it just pass is there something wrong with me!?? plz help i really dont know what too say to my partner!