Light brown spotting 4 weeks pregnant

Ma
im 4 weeks and 1 day pregnant and spotting light brown with white watery cm mixed this morning. No enough to go on a pad no cramps etc. My period would have been due today or 4 days ago depending on which cycle 26 or 29 days. I had a positive test very strong positive a week ago and took progression photos until yesterday abd it was darker. ( i have attached the photo) im just so worried...am i miscarring? Is it normal?