Hi thanks for your question.
No, you are not pregnant. The day (first day after your periods) you had sex with your husband was your safe period and chances of pregnancy
are nil. The most common causes which can give rise to bleeding after your normal cycle are;
No. 1 could be cervicitis
that is inflammation or infection of cervix .The second could be fungal or bacterial infection of the vagina. Third could be a fibroid
of the uterus. Infection anywhere in body can give rise to increase headache and increase in heart rate
. The little ball which you’re feeling in your lower abdomen could be a fibroid in uterus, which could give rise to this abnormal bleeding along with abdominal cramps and headache. Consultation with a physician is advisable who may perform your physical examination and may advice you ultrasound
abdomen to rule out or confirm fibroid uterus as a cause for your symptoms.
Hope this answers you question.