I had a mini seizure when I smoked that legal weed k4/k2 should I get a cat scan done on my head?

Maybe something else. If you are feeling alright now, you do not need a CT scan. If you are sure it was a seizure, you should first visit with a neurologist, then perhaps other tests would be helpful. For seizures, blood tests, MRI and EEG are helpful. But what is a mini seizure? That is important too. Avoid k4/k2. That stuff causes odd symptoms. Stay away.
Probably not. Talk about it with your physician during your next annual, or make an office appointment should something like this recur.
Couple of things. First, don't smoke bizarre chemicals. Second it's not clear what you're calling a "mini seizure," so (third) it's hard to recommend any specific test or treatment.
Yes. What was your seizure like. It is not safe to assume it was due to what you took. Most physicians get an MRI if this was the first time!