Headache after PDO outer brow lift?

I had a PDO Brow Lift (outer area) one week ago. It looks very natural and I am happy with the results. The swelling is almost completely gone (I can see elevated lines going upwards from the brow to the hairline). The only thing that has been bothering me is the constant headache, similar to a mild migraine (temple/eye area). How long does it take for the headache to go away? Thank you very much in advance.