Red Bump On Forearm, Tender, Swollen, Relief With Acne Medication. Hand Numb, Sore. Medical Attention Required?

Hello, on Sunday afternoon (2 days ago), I noticed a red bump on my left forearm, at the middle. It felt tender and swollen to the touch, less than the size of a dime. It also hurt to touch it. I put some acne medication (salicylic acid with chamomile) on it overnight. The next morning, the swelling and pain had reduced, but there was a pimple (small pustule) on it, still with redness. I washed off the medication. Now, in the night, I begin to feel some numbness in my hand. It's similar to when your foot falls asleep, and you have to squeeze/massage it a few times to feel better. Except my hand doesn't feel better. It feels pretty sore, and numb. Although the pimple and redness have now greatly reduced on my arm at the original bite (?) site. Please inform me of a possible explanation and whether I should seek medical treatment/attention at this point? Thank you in advance.