I’m afraid I’m having a chemical

I found out on Thursday 7/14 that I’m pregnant and the line was pretty light

Today on 7/19 I was worried cause I’m not having any symptoms so I took another test which is significantly darker

So I thought I was in the clear but now I have a very small amount of light brown discharge and that is something that is typical for me the day before a period.. has anyone experienced a chemical even though the lines were getting darker?