Are there no side effects to Botox?

I have never had Botox before.
I used to have some reservations, but Botox has become very common these days.
So I keep thinking I should try getting it too.
But by any chance, are there any side effects from Botox?
I suppose Botox isn't dangerous, but I have this unnecessary worry that it might not suit me, just like an allergy.
Nevertheless, the sense of depression I feel when looking in the mirror is quite great.
Still, I want to try getting Botox at least once in my life.
I also feel a desire to see the changed face.