Hello, and sorry to hear about the issue you experienced following Dysport treatment. In general, side effects from Dysport injections can include the following:
1) Bruising
2) Headaches
3) Eyelid ptosis
4) An expressionless appearance - (if too much is injected, or the injections are not performed properly)
5) Minor swelling
Duration and onset of side effects can vary from patient to patient, but generally will subside following a over a few weeks to months.
In addition to these side effects, the brow can be elevated. You can have another treatment to help fix your issue. In your particular case, about 5 units of Dysport can help relax the brow to a normal position. It is important you choose an experienced injector for this, as you do not want the injections to be overdone. This may cause brow or eyelid ptosis to take place, and leave you with an entirely new problem. I hope this helps, and good luck to you!