Why are the test strips showing weak positive results every time?

Patient's question:

Patient Age: 28
Detailed Condition and Purpose of Consultation: Not pregnant for one year after marriage. Menstruation came on the 8th of last month, but it hasn't arrived today (17th of this month). Why are different pregnancy tests showing weak positive results several times? Is there a possibility of pregnancy??
Duration of Current Illness: 40 days

Doctor's answer:

If only one purplish-red control line appears, it is negative; if another purplish-red test line also appears, it is positive. If the test line color is lighter than the control line, it is called a weak positive pregnancy test result. As long as two lines appear on the test board, it indicates a possible pregnancy. For weak positives, it is recommended to repeat the test in about a week, or consult a doctor in the gynecology and obstetrics department for further guidance.
Recommendation: If menstruation is delayed by more than one week, it is advisable to visit a hospital for an early pregnancy test to promptly determine if you are pregnant.