Aiyo, I can feel your worry lah, three days of overthinking must be so stressful for you! Since your UPT is showing positive, the brown discharge could be implantation bleeding (which is actually a good sign in early pregnancy), but it can also mean other things, so it's really best to call your doctor or clinic to check properly, especially since you're spotting and feeling uncertain. They can do a blood test to confirm your hCG levels and make sure everything is okay, which will give you proper peace of mind instead of all this guessing. Try not to stress yourself too much in the meantime, I know it's hard, but your body needs rest right now.