SOMEONE PLEASE HELP ME UNDERSTAND

So, I was last on my period on the 28th November and it lasted like 1 and half days/2. After that I had the worse backache (lower) for days where I could even move at times.. When would you say I was due on my period now?? I still haven't come on, but I'm having period type pains and my boobs are killing (normal symptoms) should I redo a test in the morning? I did one this morning and this is the result, it's a little pink in real like but I believe this is a Evap line.. can someone please help me.