Can Botox have the opposite effect than desired? (Photo)

I had my first Botox injections and after 2 weeks my lids are droopier than they were prior to treatment. At first she cited that I reacted with swelling but it has not subsided.The injector told me that I am 1% of cases where I am sensitive to Botox (she used 20 units above my outer brows & said she would use less if I attempted again). She said I now have to wait the 3-4 months so I look "normal" again without the excess lid heaviness and I am simply not a candidate for Botox.