Welcome to healthcare magic.
Thank you for your query.
Though the chance of conception is less but you have to exclude it.
You should check urine for HCG
become delayed but 20 days is too late.
Brown discharge with jelly like fluid should be evaluated carefully.
PID or sexually transmitted disease
is one of the possibility.
It is better for you to consult a gynecology & get examined.
I hope I have been some help of your query.
Please write if you have any doubt.