Could I be pregnant

Okay so im 17 and im 24 days late for my period(freaking out) I last had sex on the 16th of November and I have had 3 periods after on time. I hsve take 4 tests all in the morning however on diffrent days of last month and this month all of them have come up negative even the digital one. My next period is due the 31st of this month, what should I do?

Vote below to see results!