Advice please re periods and morning after pill

[ShouldHaveMoreSense]

I need some advice please. I have no idea of the date of my last period, only that it could have been around 3 weeks ago. I had unprotected sex on Sunday 27th September and I took the morning after pill on Tuesday 29th.
From Saturday past I have had very light bleeding, so light that its only noticible when wiping (sorry tmi), and that seems to have stopped today.
I know there is every chance that I could be pregnant. Is it likely that I am, and when should I test?
I dont feel pregnant. In the past I have always guessed that I was before my period was even due.
Thanks in advance

its highly unlikely that you will be pregnant but the high dose of hormones may just have upset your cycle and given you a bit of 'spotting'. Do a pregnancy check

Thank you for the reply. I had been worried that the delay in taking the morning after pill would increase the risk of pregnancy. I know I will have to do a test to put my mind at rest. I will take one later in the week if nothing else happens.