Im so confused

Morning Ladies! I found out 3 days ago that im 2-3 weeks pregnant, after being 2 days late on my period. I wasnt trying so it came as a bit of a shock, but happy none the less. I took 2 clear blue digital tests. both came up pregnant, 2-3 weeks. This will be my second child... Our first was born in 2012, so i feel out of touch with it all. We didnt find out we were expecting her until i was 7weeks. My confusion is literally down to the information ive been reading... how can a test say im pregnant, but all these apps etc say The egg hasnt even implanted yet, you might not be pregnant etc... If anyone can shed some light on this. I'd be very greatful! Thanks in advance 💚