Evap line?

I'm really confused. I've been on the mini pill for 2 months now but last week I had some slightly pink discharge with abit of spotting. Over the past 3 days I've felt really nauseous all night and have to eat as soon as I wake up or I'm close to being sick. I've had loads of cramps too. But tests keep coming back negative. I feel exactly as I did when I was pregnant with my daughter. Because I've been on the mini pill though I don't know when a period is technically due as they have been quiet irregular