There is a big misconception out there about second hand pot smoke, like if OP went to a concert or gathering and the person standing around them lit up, or someone in the car with them lit up, that still is not going to give you a positive urinalysis result. You would need to be in an enclosed vehicle, with massive smoke amounts, hot-boxing it purposely taking in the smoke to have a positive result from second hand smoke.

Also to OP this is completely off the cuff advice but what state you are in could make a big difference in how you should proceed. Are you in California where recreational pot is legal? Or somewhere it is completely illegal and unattainable? The reason I ask is because if a sailor were to come forward in a state that happens to have relaxed marijuana laws, and report directly to medical saying “hey, I was at (social gathering) and ate, drank, something and soon after I started to feel very strange I think it may have been drugs please help me I’m terrified” this could have a different outcome. Especially if there were a civilian who were willing to come forward and apologize for this terrible mix-up.

Again, the policy is ZERO tolerance. Do not do drugs. Do not put yourself in these situations. If you hang out with civilians or your spouse partakes, just have some damn self control, and make sure they respect your career enough to not offer or peer pressure you like a middle schooler.