You must avoid heavy lifting for at least 48 hours. It takes a day or two to get back to normal. Sex can resume when it is no longer uncomfortable. Therefore, it does not affect your masculinity or ability to achieve an erection. Sterilization IS NOT castration.
Castration is the removal of the testicles.
Since a vasectomy does not involve the nerve or blood supply to the penis, there is no reason for impotency after the surgery. Your testes will continue to make sperm. They are absorbed by your body. This is true whether or not you have a vasectomy. The body absorbs unused sperm cells.