23123(A) Violation. How Are My Chances in Court with This Evidence

Charged with talking on cell while driving in San Diego, CA
Here's my version of events:
• Driving along eating a big slice of pizza (could have looked like a phone I guess )
• Flashing red lights, I pull over
• While officer explains why I was pulled over my phone rings.
• I answer the phone and explain that I am unable to talk.
• Officer says: "See I told you you've been talking on the phone".
• He writes the ticket. Time of violation recorded as 3:50 PM.
• I make a couple nervous calls (while parked) and drive away.


My VZW call log:

Note that the middle three calls are all to the same number. (Mom)


Assuming he remembers/is honest about witnessing the incoming call, I see two possibilities:


1) He agrees with my claim that the incoming call came at 3:49
The call log shows no earlier call, therefore I am innocent.

2) He claims the incoming call came later.

He would then have to claim the following:

• He pulled me over for the call at 3:49.
• After getting my info he went back to his car to write the ticket.
• While he was away I made a two minute outgoing call at 3:55 that ended just before he got back to my car.
• He returned, and immediately observed me answer a call at 3:57 as he handed me my ticket

His scenario sounds plausible, however I am certain that the incoming call came prior to the ticket being written.

I don't want it to end up his word against mine.

Any advice?
Thanks

PS
I realize answering the phone with him there grilling me was stupid, I was nervous and not thinking straight.