Hi LW. Not to worry, this will correct itself after a short period of time. One of the side effects of Botox injections is Ptosis. This normally happens with less experienced injectors as injection technique and amounts are important in avoiding this problem. We suggest you visit your injector to see if they can help with the problem by doing a "chemical browlift", but if you do not have confidence in your injector or they don't normally offer this service then it may be best to just wait. Good luck.
Web reference: http://www.celibre.com/botoxBrowlift.aspx