I think I got bit by a bug and I think its infected how do I know

You think?

What makes you think this? We can't see it so we don't know what it looks like. You can get some idea by looking to see if you got a bite somewhere...a raised bump or something...then is it discolored and painful?

Maybe you should just see a doctor to be safe if you aren't even sure if you got a bite or if it's infected.

I got a raging infection from a bug bite behind my knee; I didn't even know it was there. It was a big white volcano with a big hole, big enough to let bacteria in. A rash spread quickly to the front of my leg, and even after 10 days of oral antibiotics, it spread all over my leg, and like several other regulars on this site, I ended up in the hospital with cellulitis.

The first thing you do with any scratch or bite is wash it with plain old soap and water. That prevents most infections! But once infected, you have to see a doctor.

How do you know? Extra redness, pain, spreading rash, or pus.