Hello, I've Been Taken Zoely For About 2 Years Now

Hello, I've been taken Zoely for about 2 years now and this is the first time I didn't have my period. Last year around this period it was lat of 3-4 days but I didn't have a partner and I was sure nothing happened. Now I have a boyfriend and I took all the pills, I just forgot one one evening but I took it very early the following morning. Should I be worried? I took 2 pregnancy tests and they've been both negative but I'm not sure if I can trust them...