I got bit by something on my foot is swelling, itchy and red. how can i figure out what bit me?

Wrong Question: It does not matter what bit you. What matters is if this swelling red lesion is an infection, abscess, or something much more dangerous than just a bite. Swelling makes me believe you need medical attention urgently. Don't you think?

You can't: There's no way to determine which bug bit you unless you see it. Many types of insects cause swelling, itching and redness. In terms of treatment it doesn't matter much - you just take some claritin (loratadine) or benedryl. If the swelling gets worse or pain increases then you see a doctor for possible infection.