Thank you for your question hodana. Botox is a treatment used to address wrinkles on the forehead and elsewhere on the face and neck. Usually a small bump is seen at the injection point for about an hour or two after a treatment. This is from the product being injected into the skin. But this resolves quickly. I recommend speaking with your doctor if anything lasts five days. Good luck!
It is hard to to determine if this is a bruise or something from the botox. I would follow up with the injector and she/he may be able to determine what caused the lump.
I suspect that the bump maybe related to residual frontalis muscle activity. I would wait 14 days for the Botox to completely kick in. If the bump remains at that point, I would followup with your injector. He/she will likely want to see your forehead activity in person and will determine whether you need additional units. I wouldn't worry about it at this point. Wait the 14 days.
It will take about 10-14 days for your Botox to take full effect. At that time, it may be easier to decipher if the bump is from muscle movement or some other issue. For now, allow the swelling to come down which will take about 2-3 weeks. Additionally, relate your concerns to your injector as soon as possible and possibly schedule a visit for further evaluation.