Update: We saw the dr. Tues night and J possibly has a staph infection. The dr. was pretty concerned but let him start on oral antibiotics and we had to go back last night to get it rechecked. She drew a line around it to mark the edges so we could more easily see if it was getting bigger. We also had to soak his finger in lukewarm water 2-3x per day. Thankfully, it was looking better (to me and to my daycare provider) after 2 doses of the antibiotics though the dr. didn't think it looked that great. Though after talking about it, she did agree that it had certainly not gotten worse and some of the redness had gone down. We are continuing the treatment and will get it rechecked on Friday.
I'm still unsure what caused this, but my reading on staph infections is that they can occur with no noticeable injury. So maybe just bad luck.
staph infection! yes that's what i get sometimes. I have only had them a few times, but I think generally it's just bacteria gets into an open wound, such as a cut from poking your finger. the one i got under my armpit was probably due to shaving, and the one i had break all over my back(didn't help i popped one haha) shortly after getting a tattoo was probably due to some bacteria getting on it during the healing process (at the time i was living in a basement that wasn't very...clean. it was clean but my bed it turned out was under the window that leaked during the rain so there was mold going that i didn't know about til a few months later).
i'm sure with the antibiotics and dipping it in water like you're doing will make it go down. they only cut and drain them if they are really bad. glad it's getting better!!