Почему во время менструации у меня выделяются гелеобразные сгустки?

It sounds like you may have a yeast infection. If you have an infection, you may not get your period as a result of a hormonal imbalance. Yeast infections are often accompanied by white discharge. For relief, try using over-the-counter antifungal creams or pills. To avoid further infections, always practice safe sex from now on. 

There is a risk of pregnancy when having unprotected sex, even without ejaculation. Sperm can be released beforehand, which can lead to conception. If you miss your menstrual cycle or experience symptoms like nausea, it could indicate pregnancy. In such cases, considering emergency contraceptive options would be a wise step.

A woman could be pregnant if she gets a menstrual cycle after having sex for 11 days, but other times, this is not the reason behind it. You can see cramps in this regard or some bleeding that is not typical of a period. This may be due to the changes in your hormones, or there may be other issues that have lead to this. To diagnose the situation, it's advisable to take the pregnancy test a few weeks after the last time you had sex. Although it's not necessary to have periods after 11 days each month of the sexual act, it does occur sometimes, but it's not always indicative of pregnancy. 

menstrual cycles do vary slightly from month to month & changes in the timing or length of periods is due to stress, hormonal imbalances, or other health conditions. There is nothing to worry about, but if you experience persistent changes in your menstrual cycle consistently early or irregular periods it's better to talk to a gynec.