I had a browpexy and I wonder how long it takes for the bump to go away under my skin? (photos)

It sounds like you had an endotine implant placed to lift your brow.  If so, the implant takes 6 - 12 months to reabsorb.  I don't commonly use this device anymore but have seen patients that feel no discomfort during this time and others that are bothered by the implant. In the first few days and weeks after the surgery it is very normal to have swelling and discomfort, and this generally subsides no matter what approach or implant was used.  You should have a follow-up visit with your surgeon scheduled for the near future and that is an opportunity for you to voice your concerns. 

After browpexy it is quite common to feel a bump on the lateral aspect of the brow area, whether it was done with an endotine implant, or with a suture. These bumps tend to get better in the first few weeks after surgery, as the tissue becomes less swollen. Warm compresses usually help with expediting this process.You should follow up with your surgeon to voice any post operative concerns, and so he can follow your progress.

Please remember that you are only 5 days from your surgical procedure.  It takes a few weeks for resolution of the swelling and bruising after a lift.  Some residual irregularity will persist longer depending on techniques utilized.  No worries.  Check with your surgeon.