Thanks for all the replies guys.
I really am stumped because my phone is also connected to my email so even if a hacker could get into my email account to delete any incoming messages, I would of got a ping to notify me that someone had logged in with a new IP.
I've gone through all of my emails, nothing, I just can't figure it out. I am going to try and contact Bittrex and see what they say. I was using someone else's internet as I was round a friends house on Boxing day and stayed the night, but even then I'm struggling to put the pieces together.
It's really just a very odd situation.