COMMON MENSTRUAL CHANGES
One of the common adverse reactions to this medication is a change in menstrual periods. Approximately 30 percent of women in clinical trials experienced heavier menstrual bleeding after taking a Plan B tablet, according to the Plan B prescribing information. The Plan B prescribing information also notes that approximately 4 percent of women experienced a late menstrual period after taking Plan B. Menstruation for these women occurred over seven days later than expected.
OTHER MENSTRUAL CHANGES
Some women also experience periods that are lighter than usual or come earlier than expected, according to the official Plan B website, but these reactions do not happen as frequently. Spotting may also occur.
CONSIDERATIONS
Plan B may also cause other temporary side effects, some of which may accompany the altered menstruation or spotting and be mistaken for changes to the period. These side effects may include nausea, tiredness, headache, dizziness, breast pain or vomiting, according to Drugs.com. Women who vomit within one hour of taking the Plan B tablet should contact a doctor, as the medication may not have not had time to work and they may not be protected against pregnancy. Any woman with questions or concerns about side effects should contact a doctor.
Also implantation bleeding is a pinkish or brownish in color. Never bright red with heavy cramps.
one of the side effects is bleeding it can also make your period come early. If you were pregnant you wouldn't have heavy bleeding and 7 days after sex you would not be feeling any pregnancy symptoms cause it can take 7-10 days foe the egg to implant and even then your body doesn't even know that it's pregnant yet. So no your not pregnant the bleeding is because of plan b throwing off your cycle.