My question involves a speeding ticket and failure to signal lane change from the State of: TEXAS

I got a speeding ticket and when the female officer came up to the car that is what she said - I was speeding. I stupidly said then so was everyone else because I was going along with the traffic flow as I handed her my license. When she came back she also gave me a ticket for failure to signal lane change. Which had to have been when I was moving over after she came up behind me with her lights on. The traffic was relatively light and she was the only car that I really had to worry about. is there a way to defend myself against that kind of abuse except perhaps to say I was so flustered by the ticket lights that I forgot.