Hallow Dear,
Body play and just touching the penis to the vulva will not cause
pregnancy nor will they cause any alteration in menstrual pattern.
You are having
irregular menstruation even before you had this body play. The type of intermittent bleeding you are having is likely to be a variation of the irregular menses.
Before you take any medicines for controlling this bleeding, I would advise you to get
ultrasonography done to find out any abnormality or lesion in the
uterine cavity. If there is any pathology in the uterine cavity, it will have to be treated. If there is no pathology in the uterine cavity, you can control this bleeding by taking some Progestational preparation like
Deviry with the advice of a Gynaecologist.
Once the bleeding has stopped, you may start oral birth control pills for three cycles. This will help you regularise your menses. Of course, the pills should be taken with an advice of a Gynaecologist only.
So, please report to your Gynaecologist.
Dr. Nishikant Shrotri