should i be concerned?

my heart is beating weird. It feels like its beating kinda fast but I'm not doing anything. I was just sitting at the dining room table doing some homework after my shower. i told my sister in an IM and she told me i should tell Loro but he's sleeping and I don't want to wake him up if im imagining it. i probably had too much caffeine today or I need to cut back on the amount of food I eat. Come to think of it, I did have 1/2 a 4 max. it may be nothing, but my imagination. I don't have any other abnormal symptoms so I'm just going to let it slide.