Hi,
As you have described, you are in safe period and the chances of
pregnancy is very less. This method, called as calendar method can also have failures and pregnancy cannot be ruled out completely.
Another important information is that the precum at times can contain sperms and pregnancy can occur even if the ejaculation was done outside.
Considering that you were in safe period and only exposed to precum as per your description, the chances of pregnancy is extremely less. So you can take risk and wait for the next period.
In case you do not want to take the above risk, you can consult an obstretician for emergency
contraception. You will be prescribed medication that contains
levonorgestrel and has to be taken within 72 hours of unprotected sex. Sooner the better for this medication.
If you were my patient, I would have recommended you against pills as the risk is ver less. Additionally I would recommend you to use barrier or any other method of contraception over getting stressed about pregnancy.
I hope the above information helps you. Thanks for writing into healthcaremagic. Have a wonderful day.