2WW...

Hi guys, 
I think I'm going out of my mind at the moment and getting random symptoms that might be in my head! AF is due 1/1, on 22nd Dec there was a small amount of dark CM  on my underwear which I would think was far too early to be IB as I was only 4dpo. My boobs started to hurt a little that evening when I was running from the car to the shop which I got a bit of a shock about. Since then I have travelled home for Christmas so have dramatically changed timezones. The past few days I have been exhausted (could be jet lag?!) I'm waking up a lot at night and have minor cramps but only at night time. 
Last night I felt like I was getting AF so I did a quick CM check and it was a very faint pink colour (10dpo). There wasn't much of it, I used a tampon last night and this morning there was a very tiny amount of brown CM on it. 
When do you think I should test, obviously the time difference change should make a difference to my cycle right?