Hi. For The Past Few Months I've Had A Bump

Hi. For the past few months I've had a bump on my penis shaft. I thought it was an ingrown hair because I once shaved against the grain and that spot hasn't been the same since then. I recently poked at it with a sterilized needle and I was able to extract a long dead hair. But now it looks like a small bubble with clear liquid inside it. What is it?