Why is my period late and pregnancy test negative?

An HCG level of 2622.43 mlU/ml indicates a positive pregnancy test. HCG is a hormone produced during pregnancy, and its presence in a woman's blood or urine is a strong indicator of pregnancy. However, the HCG levels can vary widely between individuals. 

Having sex close to your period may pose a pregnancy risk because the sperm can last in the body for a few days. You're most fertile around ovulation, but it's hard to tell the exact time. If you miss your period or have symptoms like nausea or breast tenderness, you may want to take a pregnancy test. 

Your period's regularity could result from anxiety, hormonal shifts, or perhaps pre­gnancy. Signs might include abdominal bloating, me­nstrual-like cramps, and tender bre­asts. It's wise to be patient, se­e if menstruation begins. If it doe­sn't, consider getting a pregnancy test for de­finitive confirmation.

Painful headaches, vomiting, and pale face during periods - common. Vitamins and folic acid may not work. Consult a doctor immediately. 

Multi-cystic means urine is filled inside the baby's kidney. These renal anomalies would start to show up around the fifth month of pregnancy. In most cases, this is not harmful to the baby and it can get cured on its own.

Always consult a doctor before using tablets to change your period. The menstrual cycle is a natural biological process, and altering it with pills can harm your health. While it’s understandable to want to adjust your period for events like a cousin’s wedding, it’s important to let your body follow its natural cycle whenever possible.

You are concerned about preventing pregnancy after one month. If you're afraid it will happen, then the best way to prevent it is to use emergency contraception. This can prevent pregnancy even after unprotected sex. It's important to act quickly and take the emergency contraceptive pills as soon as possible.