It is impossible to know whether the bleeding occurred because of premenstrual spotting or implantation blood without a physical examination. To get a clear idea, plz visist a gynecologist

In this case there's no chance of pregnancy.

Puberty can start at different ages for different people and there is a wide range of what is considered normal. 
The ability to have children (reproductive maturity) usually occurs after the completion of puberty when the reproductive organs, such as the ovaries and testes, have fully developed. For most individuals, this occurs in their late teens or early twenties. However, it's important to remember that everyone's development timeline is different.

its common to miss periods after stopping the pill for pcos.. HORMONAL imbalances cause irregular periods.. CONSULT a doctor if the absence of periods continues.. they may recommend MEDICATION or LIFESTYLE changes to regulate menstrual cycles..

CONTINUE taking 50 mcg of thyroid medication during pregnancy as TSH levels may fluctuate during pregnancy!! Lowering medication may harm the baby. Consult with your DOCTOR before making any changes.

It's unlikely that your fiance is pregnant Birth control pills alter hormone levels, which can cause lighter periods. However, if you're still concerned, take a PREGNANCY test or consult a doctor Remember, birth control pills are not 100% effective at preventing pregnancy, so it's important to use additional PROTECTION if you're not ready to conceive. 

Symptoms you may be experiencing can be due to hormonal changes, which may not be indicative of pregnancy. An irregular period can cause the hormone levels to fluctuate, leading to tender breasts, bloating, and mood swings. Stress, diet, and lack of exercise can also be the reasons why your body is affected this way. Try managing stress, eating healthy, and gentle exercise to help balance your hormones.