I had Botox 2 weeks ago and have broken out in pimples all over my forehead?

I had Botox about 2 weeks ago and a top up 1 week ago. The first time I was injected there was no issue however, I have since broken out in small whitehead like pimples over my forehead. This has happened before just after my botox injections and think it can be managed. My question is how can I help treat these without using acne treatments or harsh treatments? Also could this be the type of Botox used as I had them done a different places, I think they have used different products? Thanks