Please anyone!?

So my last period started November 29. I then had sex 17th of December. It was protected. No issues with the condom. He also used withdrawal, and did not come inside me. We did however panic and take plan b the 18th of December. My next expected period was the 28th of December. And on the 27th I had bleeding when using the bathroom. It was red like a period but never came out onto the pad (weird for me) for the 6 days it lasted. I know plan b can mess up your cycle and period but i did test the 28th (Negative) and January 4 (Negative) it is now 19 days after sex. Did i test to early or should i trust the test? Please don’t hate on me I know I panicked. Just in need of some girl advice