It is possible to acquire tics after brain injury.
One example from PubMed below...

http://www.ncbi.nlm.nih.gov/pubmed/21534741
Brain Inj. 2011;25(6):629-33. doi: 10.3109/02699052.2011.572944.
Tics after traumatic brain injury.
Ranjan N1, Nair KP, Romanoski C, Singh R, Venketswara G.
Abstract

However, you describe slurred speech, confusion, memory problems and going limp.
Were you having the movements when you had the EEG?
Did they suggest an ambulatory EEG? That's one you can move around with and take home and it monitors you over a much longer period of time.