Feeling depressed and low the last couple of days

So a day after work something hit me and felt really down and stressed. I didn't feel too bad at work just a bit anxious but I think spending 2 days not sleeping didn't help and I was very emotional and ended up crying a lot and feeling kind of helpless. I'm oing over to my mum and dads today so hopefully that might help and I've got an  appointment  with my GP tomorrow so I guess we'll go from there.