Hi welcome to the health care magic
I will solve your query and will give my opinion in this answer.....
Let me explain you false positive urine card test causes......
_
abortion history in last 6 week
_Test not done as per kit insert
_reading not taken in prescribed time in kit insert
_expired kit
_urine contamination with blood
_trophoblastic tumour etc...
I advise you to repeat urine card(at home) or blood
hcg estimation done (at hospital)
I need to know USG done by Transvaginal route or transabdominal route??
Tvs
sonography able to visualize
gestational sac 5 week after LMP if conception occured
And for Transabdominal time period is 6 week after LMP
Urine card positive 5 week after LMP
And remember USG confirmation needed to rule out
pregnancy Hope I have solved your query
Take care