On your tod
Definition 1 of 1
Pro Tip 1/3British Slang
Understand it's a British slang phrase and rarely used in other English-speaking countries. 
When I moved to London, I learned that 'on your tod' meant spending the day alone.
Pro Tip 2/3Colloquial Use
It's casual and best used in informal situations, not in formal writing or speech. 
After the party, I found myself on my tod, so I decided to walk home.
Pro Tip 3/3Feeling Isolated
Can imply loneliness or the fact that someone is doing something without company. 
She felt a bit on her tod at the new job, since she hadn't made friends yet.