Hi and welcome. Acquired brain injuries come fom various sources, where a Traumatic Brain Injury (TBI) is defined as an alteration in brain function, or other evidence of brain pathology, caused by an external force.
http://www.biausa.org/FAQRetrieve.aspx?ID=43913
I'd say a poisoning that caused brain injury qualifies as an "external force". More importantly, this is a place to seek support and share experiences.
The fact that you are "able to get better" doesn't mean you don't have a TBI, ABI, or that you don't belong here. If I wasn't "able to get better" I'd be in a care facility somewhere wondering what happened and what year it was.
Stick around, ask questions, and share your experience with us.