Baby #2 after 8 years pp

So I just turned 24 yesterday and I took a test on the 1st which came back negative. Tested again on the 8th and test immediately came back positive like dark positive no faint lines or anything lol but I just feel so weird because my son is 8 and I jus kinda always thought it would jus be me and him forever but does anyone have any tips and has anyone ever experienced this much of an age gap between kids, also how soon did you all start showing with your second pregnancy