Hi,
Thanks for the query.
If you have regularly been taking birth control pills then
pregnancy is unlikely. It seems from your query that you are taking pills for 28 days of these 21 are active and 7 inactive pills. Periods usually start after 3-4 days of beginning of the inactive pills. I suggest that you check your pack of pills to see if they are 21 or 28. If it is a 21 days pack you need to stop pills for 7 days.
You must repeat the pregnancy test after 7 -10 days. If it is negative and you use a 28 days pack, I suggest that you continue your pack for this month and see if the periods come during the inactive pills, if they do not come other causes of need to be ruled out. Check to see if you have been experiencing too much
stress or have lost or gained weight. Also check to see if you have any discharge from the nipples as all these can cause absence of periods.
There are certain other causes that need to be evaluated like
thyroid problems or ovarian lumps. For this you will need to see a gynecologist.
The weight gain may be due to the pills. The belly lump needs to be checked if it is due to fat deposition or due to an enlarged ovary. Your doctor will help you with this.
Once again I think that the chances of pregnancy are low but if you continue to have absent periods, get yourself examined.
Hope you find this useful, Thanks for using health care magic.