in contact with blood

I was at my gym the mon evening. when came back to the canteen after my shower there was another member seated there who had hurt his finger badly and it was bleeding profusely. After about two minutes when he left from there i sat on the same table and unknowingly kept my hand there. but the minute i saw blood stains( both blood droplets and blood with water) i got up from there. but at moment i just forgot to wash my hands and ate with the same hand. although i did not see any fresh blood on my hand I am scared there might a possiblity of a droplet. There are no cuts or abrasions on my hands but what about the sandwhich i ate. what if the blood went on my sandwhich and went into my system. is there a chance of me being infected with this. i repeat i saw no blood drooping from my hand but can a li'l droplet pass through my food and infect me.
i have no knowhow about the actual status of my mouth during the incident occurred; although i do have gum problems more often, however not deep wounds which are painful and noticeable. but in a scenario where a minutest sore somewhere in my mouth was touched by the blood stained food; what are the chances of infection. i know i am getting hypothetical but just need comprehensive info to put my fears to rest. i never licked my fingers while eating my food.