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Check for any changes in your baby's fetal movements, becuase it can decrease its oxygen supply. Contact your gynecologist immediately.

While using an emergency contraceptive pill might decrease the risk for pregnancy following intercourse, it does not offer a 100% protection. A visit to a gynaecologist should be made for further instructions and follow-ups.

You may be experiencing a vaginal infection, which can cause discomfort. Symptoms of a vaginal infection can include an unusual odor, itching, pain, or abnormal discharge. These infections are often caused by fungi or bacteria. To address this issue effectively, consult a pharmacist. They can recommend specific pills or creams to treat your condition, leading to noticeable results. 

The Last Menstrual Period (LMP) calculates gestation from the start of your last period, while gestational age by Biparietal Diameter (BPD) or Femur Length (FL) measures the baby's size. The difference in weeks might be due to variations in fetal growth rates. Your obstetrician can provide more insight and guidance based on these measurements. It's always best to consult them for a clearer understanding of your pregnancy progress.

Normally, implantation bleeding is lighter and shorter compared to the usual menstruation flow. A negative HCG test could mean that it’s not a case of pregnancy. The tests may have been carried out too soon for the existence of any pregnancy to be detected. 25 days may also be too soon for an ultrasound. So it's either way too early for these tests or the likelihood is that you are not pregnant. Keep an eye on the symptoms and repeat the test after a week or two for better results.

On average, the menstrual cycle lasts from 3 to 7 days. There are pregnancy possibilities even if having sex at any time, but the chances are greater during ovulation, which usually occurs on the 14th day of a normal cycle. If your period started 4 days ago and you have a 28-day cycle, ovulation could be in place now. 

Experiencing a burning sensation in the urine and vagina for three months could be due to urinary tract infections, vaginal infections, or other medical conditions. See a doctor promptly for a proper evaluation and appropriate treatment. Avoid delaying as untreated conditions may lead to complications.

In this case you should go for second opinion of another experienced doctor. They can evaluate your case and then you can come to a conclusion.