Missed period

So I was living with my boyfriend for all of November and December and got both those periods on time but December was abnormal and I didn’t have any regular symptoms. 2 weeks after it ended I noticed I was spotting whenever I wiped after going to the bathroom which has never happened before… I’m now 11 days late for my January period and have taken 5 pregnancy tests… there are stress factors involved but should I keep taking pregnancy tests even though they’ve all come back negative?