Are Muscle Spasms in Forehead After Botox Treatment for Migraine Normal?

I had my first Botox treatment for migraines two months ago. The areas treated on my forehead were along the hairline and between the brows. One of the sideeffects was smoothing out of the center of the forehead but not the surprise lines above the brows. Almost 2 months after treatment I began to experience involuntary muscle spasms above the brows and now between the brows. The spasms can also be triggered by rubbing/pressing the forehead. Thanks for your thoughts.