Sad, worried, what can I do? Help! 😢

So I have been testing since Friday and have been getting positives and this morning when I tested, there's barely a second line and I tested 3 times and on all three it either looks negative or vvvvvfl like its going away. Im 9 days late with cramping, lower back pain, nausea when I eat and fatigue. I dont what this means. This will be my second pregnancy. Im so worried, I feel like going to get checked at the ER but I dont know. Im stressing out so much, Im crying my eyes out now!