What's Wrong With My Franklin?

While coming back from Oakland on the Bay Bridge, I presented a $100 bill to the toll taker for the $4 toll. 

The toll taker did the usual, holding the bill up to the light to see the water mark and the pen to test the bill to see if it's real. 

Then suddenly she had this look on her face.  She took the bill and wrote something on it and then something on another piece of paper then placed the bill in a seperate envelope. 

She then walked in front of my car and took down my license plate.  I asked her if anything's wrong.  She did not say anything except give me my $ 96 change and off I went.

Was that $100 bill a fake?

Uh-oh...now I'm worried.  I Googled 'What to do if you have a counterfeit bill' and came up with thisarticle.  The toll taker did everything the article said about coming upon a counterfeit bill.**** 1. Do not put yourself in danger.

1. Do not return the bill to the passer.

2. Delay the passer with some excuse, if possible.

3. Observe the passer's descrīption - and their companions' descrīptions - and write down their vehicle license plate numbers if you can.

4. Contact your local police department OR call your local U.S. Secret Service Office.

5. Write your initials and date in the white border area of the suspected counterfeit note.

6. Do not handle the counterfeit note. Place it inside a protective cover, a plastic bag, or envelope to protect it until you place it in the hands of an identified Secret Service Agent.

7. Surrender the note or coin only to a properly identified police officer or a Secret Service Special Agent, or mail it to your nearest U.S. Secret Service field office.**** Oh shit...now I'm probably going to get a visit from a secret service agent asking me about this bill...where it came from and all that.  Worst yet, they'll come to my house and turn my house inside out.  Arrest me and interrogate me.  Water board me.  Till I say yes.  Then get thrown in jail for being a counterfeiter....Now I'm paranoid.  Just my luck!