Hell, I can't even tell that you 'feel' anything. I only know that I 'feel' because I am able to subjectively experience it. I make the assumption that you feel because you appear to be very much like me in all other respects, however there is no objective measurement that can prove or disprove that assumption. Historically, not every culture even gave all human beings the benefit of the doubt on that, let alone animals (which contemporary western cultures at least often agree do 'feel').
Where you draw the line is seemingly arbitrary. Some might say that means there isn't one, that either we're all P-zombies (or at least everyone who isn't me is), or we live in a panpsychic universe. Of course, the universe has often resisted such black and white categorizations.
Consider this then: why do we care? I submit that the only reason we care whether or not something 'feels' is so we can exploit it without guilt, so we can shield our empathy from the consequences of our actions. I feel it is important to keep this in mind when making decisions which hinge on questions like whether or not something can truly 'feel'.