Confused! Could I be pregnant?

I am not TTC but, my husband and I use the withdrawal method for BC. I have been spotting like this for 11 days. Some days it’s been much less or just brown or pink discharge. This started 1 day after my period was expected but, no PMS symptoms and my periods can be 1-3 days off. My periods also usually last no more than 7 days and are VERY heavy. I’ve taken multiple PT which all were unclear or negative. Anyone else experience this? Could I still be pregnant?