What Causes Itchy Bump With Red-brown In Between?

I thought I had poison ivy. But now I don't think so. I have on bump the size of the top of a straight pin it is red-brown in the middle. And a redness around that. It had itched very much two days ago. I have used Ivarest for the itch relieve. I have gotten poison ivy so many times that I treated it in this matter. But it has not spread like it usually does. Could it be a bug bite? I was at a friends house over the weekend and there home is near water and woods.