Since last year, I've started having what I think are atonic seizures. Right now I am fourteen years old, an quite worried about this. I've done some research on atonic seizures, and most of it seems correct, but there are a few things that throw me off.
When I have my "moments," I pretty much lose most control of my body, but I have some control, unlike what my research has told me. At first I'd always drop onto the floor on something near, like from what I researched, but now I can usually stay standing when this happens. Of course, I usually have a retarded look and stature, but there are even some times where I can stay still during the seizure. Strangly though, I never have seizures when sitting, but I do often when starting to stand up. These moments also seem to last from 10 seconds to 15.

Am I really having atonic seizures? If not, what am I having? Also, does anyone know what I can do to try to prevent from having them?

Thanks in advance.