Hello
welcome to health care magic
Thanks for your query
Madam Yellow discharge is common in early weeks of 
pregnancy..
the reason for this is increased levels of hormone estrogens in pregnancy..
But if the color is thick yellow and foul smell,,then it is a sign of infection..consult gynecologist and use antibiotics for that..
Regarding another complaint pain in the abdomen it is also normal,,
Because of the growing fetus in the 
uterus,it causes the ligaments in the pelvis to strain..
So don't worry about the 2 symptoms you have described..
In pregnancy 
urinary tract infection is common,,so get regular urine analysis report..
Take iron and 
folic acid tablets as prescribed by your doctor..
Hope you understand my suggestion 
Take care of your baby
Thank you'
Dr.siddartha