This may be the beginnings of serious neuorlogic problems: a young dog that suddenly behaves bizarrely may have liver problems (I am hinting strongly at a portosystemic liver shunt, a congenital problem, but may be also acquired).
Other causes may be various tick borne diseases such as Lymes disease or Rocky Mountain spotted fever. Rabies is a serious infection. Brain tumors can occur in young animals, and environmental problems auch as lead /mercury can also cause these symptoms (many young dogs chew on and swallow a vast collection of strange items). And to round things up nicely, there is always epilepsy as a fall-back diagnosis.
Please seek out veterinary attention for your sake/health and for your pet's. I would suggest at least a basic blood panel and abdominal x-ray film to rule out an infection/liver shunt/foreign body, and a course of doxycycline to address any tick pathogen problems. If you have a rabies vaccination on board, then that is great news. Liver shunts will show low albumin, low BUN on blood work, maybe anemia, and a small liver silhouette on radiograph.
Dr. Van Lienden
Dr. Raymond Van Lienden DVM
The Animal Clinic of Clifton
12702 Chapel Road, Clifton
Virginia, U.S.A. 20124