I am 3 weeks late and I've taken 2 pregnancy tests over the last three weeks. Does anyone have any advice?

I took one pregnancy test a few days after I should have started and I took one when I was two weeks late. Could I be pregnant anyway? What are the chance of having two false negatives? Should I take another pregnancy test? I've been thinking that I'll take another one and then if its still negative, or even if its positive of course, then I'll go to the doctor. Idk what it could be if I'm not pregnant. I'm only 18, its not menopause. lol. Any suggestions?