Sharp Pain After Botox on Forehead

What you experienced is very rare. The needle most likely hit a small sensory nerve. There is not need to worry. There is no long term effect. The nerve likely has a small bruise on it that will take a few days to heal. In the mean time, you may have some symptoms like you are describing until the swelling has resolved.

Dear My, Of the millions of Botox injections that we perform each year in the field of cosmetic medicine it is a wonder that the scenario that you describe doesn't occur more frequently. At any rate, it is unfortunate that your injector struck a nerve, literally. It does happen and the nerve is bruised and traumatized when it does. It may take several weeks for the symptoms to resolve, but they will. Try not to further traumatize the area with "running the injection site". ... more

It is likely that when your doctor injected the Botox, the needle traumatized a larger cutaneous nerve. This is more likely to occur with deeper injections. You are not likely to have any long term effects but the increased nerve sensitivity can last for several weeks. I hope you are reassured.