Pregnant or Period?

I am very accurate on my cycle, it comes & goes same every month, my husband & i have really been trying to get pregnant, so days before my ovulation & day of my ovulation we did. The past 6 or so days my nipples gave been extremely sensitive & sore (not normal for me) like clock work i was to start today… i didnt start in the middle of the night or upon my first pee of the morning as usual. So i have been feeling things are different, then i had very light, pink spotting around lunch, got a tad heavier not much, accompanied with some lower back pain & light cramps…. I took a test which is iffy… it is not my normal period symptoms & extremely light for me & not any clots or bright red like usual… should i take it as a loss this time or is there still possibility?