Thanks for the query.
Some amount of breast tenderness can be seen during premenstrual phase also.
If you used contraceptive
pills regularly in previous cycle there is less chance for pregnancy
Anyhow contraceptive pills should be used as per the schedule with out relating to menstrual period.
Means in case of 21 days pills after one week gap you have to start the next pack whether you get your periods or not.
Now you can go for blood test
for pregnancy once, to confirm the absence of pregnancy. Then you can take tablets to get withdrawal bleeding. After the onset of bleeding you can go for pills.