First time Mommy here!!

Vannessa • 32 and this is my first pregnancy.
So I got my BFP on Sunday night 4/10, that was 4 days AFTER my missed period. The line was darker than I thought it would be AND it showed up quickly! I've read this is a good sign?! Right!? Based on my last period I am 4w6d. I also took a clear blue that said 2-3 weeks. Could I have been pregnant the month prior? I had a "period" but it was shorter and lighter than normal! Any help
Would be appreciated!