Based on what you described, pregnancy is extremely unlikely.
There was no penetration, no ejaculation, and you were wearing underwear. Sperm cannot pass through clothing, and prior ejaculation followed by urination further reduces any risk. Bleeding 4 days before your expected period with cramps is more consistent with stress-related hormonal bleeding, not implantation bleeding.
Next Steps
Wait for your period; stress and lack of sleep can delay cycles
If your period is delayed by >7 days, you may do a urine
pregnancy test only for reassurance
Health Tips
This situation does not require emergency contraception
Try to manage stress and get adequate rest
If anxiety around pregnancy is frequent, consider discussing reliable contraception and cycle education with a doctor