need some help ladies!!!

I am currently pregnant with my third child i did a test this morning and my lines on the test are alot darker!!! But when i was pregnant with my second and i was 8weeks and 6days but my line was only really faint!! So the question is why is it alot darker at 6 weeks than what it is at nearly 9 weeks i no i sound stupid but it's a question i needed to ask because i am a bit confused 🤔🤔