I've been anxious about my visit to the massage parlor yesterday.

My main worry is that I was given a trim and a shave to my pubic hair. This was done using a hair trim machine. She later switched to a razor. 

The reason for my worry is that both the trimmer and the razor did not seem to be cleaned. The machine in particular is used for all patients. Razor may also be multi-used. This seems to be a rather shady parlor and I regret going there. She told me I was the 3rd customer that day. They have several customers each day and they seem to be using the same razor. 

1. How likely is it that hepatitis B or hepatitis C be transmitted through the machine/razor assuming it's an infected razor. 

I presume that the trimmer and razor that you describe were electric devices.  If so, this was a no risk event bit even if they were not I would not be worried.  The instances in which hepatitis have been transmitted through shared razors involve not electric trimmers but the sharp steel razor and occurred in instances in which razor cuts have occurred.  The extension of the advice to warning about HIV, which is actually less infectious than HIV, is theoretical and I am not aware of cases in which a multi-use razor has been proven to transmit HIV.  The CDC and HIV, as Federal agencies, take a very conservative stance in their advice, reasoning that they cannot "afford" to ever be incorrect.  Further just to amplify on the previous point, statistically the likelihood that the razor and trimmer that were used on you were previously used on a person with active, untreated hepatitis or HIV is extraordinarily low.  Despite the anecdotes which are on the internet, I am confident that you are not at risk for either hepatitis or HIV and have never heard of a proven instance in which this was the case.  Thus, in response to your specific questions: