How early can you catch on that you're pregnant? What are are signs and symptoms to look out for? Whats the earliest sign to notice?

I noticed that I felt that my body was weak and lazy. Then as the time goes by, I thought it was just my hyper acidity that causes me to vomit but the color dark yellow. The following day it's again the same. I've waited for another month to confirm if I am already concieving. And YES! I am finally pregnant when the PT shown two lines. I went to soronologist right away to know how many weeks am I already pregnant and WOW! 6weeks and 6days already. 😊