Our advice for your problem is to not continue the bad decision. Although you did not know what to do, it is important to stay healthy and safe. For this reason, you should go on the good crowd, not the popular crowd. Even if you are tempted, remember our advice to do what is right for you and anyone else that will be in this situation.
The Christian advice for you is to not take the cigarette as it is wrong because in the New Testament it says that you should sacrifice your body and keep it healthy. However, in this belief it is not forbidden to smoke. The reason for this God wants you to respect your body and be happy of your looks.
In the Sikhs beliefs, one of the commandments is to not smoke, take alcohol or drugs. This religion will never let you smoke once and if you do, you will not be forgiven for your actions. You should always listen to the religion/our advice or you might never be forgiven by the god or leader of the religion you listen to.
Although you might be atheist you should listen to the advice of these religions.
Best of luck Nathaniel and Skyler
A good understanding of a range of religions and beliefs.