If you are only detained, the officer can pay down the outside of your clothing to check for weapons if there is reason to believe you may be armed. They cannot search you without your consent unless it is incident to lawful arrest. Regardless of the situation, the correct thing to do is to state that you do not consent to any searches or seizures. If they officer actually has the authority to search you, they will. If they search you unlawfully, anything they find is subject to suppression in court.

Deny them consent to search, but do not physically resist if they do. And do not answer questions without a lawyer.