Welcome to HCM,
As your pregnancy
test is negative you are unlikely to be pregnant, as these tests are very sensitive.Early morning urine sample is advised for correct results.
Your symptoms of abdominal pain
and others could be because of urinary tract infection
Take a full course of antibiotics as prescribed by your doctor.
Get one USG done to rule out any stones in urinary tract, drink plenty of water.
I advise you to have healthy food that is rich in iron and to take other supplements to correct your anaemia