This has happened to me before and has become one of my lessons learned as a client.
I would not, however, pay additional fees for him "making it up to you." I guess it could be compared to most service providers, you initially paid for the service, there were issues with the service rendered - most people do not "pay again" to fix the mistake or shortcomings of that service provider. It probably would be best to just move on if he is asking for more money, but going forward, suggest to be more direct with the feedback (i.e., would like for you to stay for the rest of the 25 minutes with me) or have that expectation clearly established during initial contact. Hope that helps.