A single episode of light brown, mucus-type spotting in early pregnancy is usually old blood working its way out, and it tends to carry less worry than fresh red bleeding, especially with no cramping. Since you're already on hormonal support for this pregnancy, mild spotting like this is a fairly common finding.
Next Steps
Please see your obstetrician today so they can examine you and confirm your pregnancy is progressing well, given the extra support medicines you're on.
Health Tips
Go in urgently if the bleeding turns bright red, becomes heavier, soaks a pad, or comes with cramping or pain.