Light brown discharge 4 weeks 1 day pregnant

Hi! I am 4 weeks + 1 day pregnant. Yesterday I noticed a tiny

streak of tan/light brown on the toilet paper when I wiped

but did not see it again after. This morning I felt around

with a Q tip and got this color shown- but after these 4

ends the color coming out on them was totally clear. My

texts this morning are progressing normally - got my dye

stealer on the FRER. On Monday my betas were 189 hcg

and progesterone 38. I have my first ultrasound and

more betas Friday (fertility dr following me due to

chemical pregnancies in the past). Is this small amount of

brownish discharge cause for concern? I'm 16 PO today.

Only mild cramping. Called dr but just want to see if

anyone had this and it was normal! Thank you!!