don't know if I should test again. advice needed please.

Amy
Top and bottom pics were this morning. Middle was yesterday mid afternoon. 
I thought I saw something yesterday when I took that test, so I decided to try with fmu. And that was the result I got. I know several people have said that they see a faint line, but now I'm actually scared to test again. 
I don't have a whole lot of symptoms, so it's very possible I am not. And when I looked back at this mornings test later today, I saw a bubble in the test that had formed near the line. Now I don't believe it was there before I tossed it, but I had issues seeing the line after the bubble formed. 
What do you think and what would your advice be?