Normal cycle 35-40 days. began spotting day 22. today (day 27) began cramping and passing clots. implantation? early miscarriage?

Menses: Cycles that are 35-40 days are not considered 'normal' cycles although it is possible to ovulate on day 25/26. If you are of reproductive age and you are having unprotected sex, pregnancy is always a possibility. Easy to test with a urine pregnancy test. If negative, the bleeding would be consistent with your abnormal menstrual cycles. If concerned, talk to your Gynecologist.

See below : Implantation may be associated with spotting. Passing clots is more likely to be your period. Day 27, given the duration of your cycle is not consistent with miscarriage. Have a healthy diet, drink plenty of water, avoid alcohol, tobacco, street drugs, and exercise at least 150 minutes per week. Get HPV vaccine.