I don’t know who my baby dad is and it’s eating me up so badly I’m so depressed

It’s killing me not knowing and I’m so worried and stressed so I had sex on the 18th and 19th with guy A of December with the same person we broke up and I had sex on the 25th of December with guy B when I went to my 12 week dating scan they told me my date of conception was the 22nd of December does that rule out guy B or is it still possible for him to be the father😓