|It is amazing how many e-mail jokes end up with rather unfunny punchlines. You are fortunate that you were only reprimanded, as the reaction in some companies to such joking around is termination. |
There is no way of knowing for sure if you have derailed your chances for success in this company, short of letting some time pass and seeing what happens. It may be tempting to go to your manager, put your cards on the table, and ask if you still have a future in the company. The problem is that doing so will keep the incident in your manager's mind, indicate that you are still distracted by it, and generate information of questionable value. The odds are that he or she will not tell you if you are toast, and even if you are told that your career with the company is still promising, you probably will not believe it. And, importantly, if you expect your career to go nowhere, that is precisely where it will go.
The best approach at this point for you is to do all in your power to be a truly excellent employee, and that is no joke.