Irregular me­nstrual cycles have various potential cause­s, like stress leve­ls or hormonal fluctuations. Precum may sometimes carry spe­rm cells, though the pregnancy risk is minimal. Some­ light bleeding might occur after taking Re­gestrone, as it helps re­gulate cycles. If concerne­d about a potential pregnancy, consider taking a pre­gnancy test. 

If you've had a positive pregnancy test and want to avoid continuing the pregnancy, consult a healthcare provider as soon as possible to discuss your options, including abortion. Follow their guidance for the appropriate procedure, and consider discussing future birth control methods after the abortion for pregnancy prevention.

SMA symptoms worsening during pregnancy is a rare occurrence. talk to your doctor

It's probably a sign of implantation bleeding, which occurs when a fertilized egg attaches itself to the uterine lining. To get the most accurate results, it is recommended to wait until about a week after your missed period to take a pregnancy test. 

There is still a possibility of pregnancy even with protected intercourse. Menstrual cycles can also vary especially if you are undergoing stress, hormonal changes, or other factors that can influence your cycle. 

Havin two periods in a month is not uncommon. The cause could be stress or hormonal imbalance. It's generally not dangerous, but consult a DOCTOR if concerned.