Supervisor announced he's going to present my work without asking permission, how can I get credited without damaging my career? Short:
My master thesis supervisor want to present my findings at a conference. He did not ask me for permission, just informed me he will do so, how should I react?

Long:
My supervisor early on said there might be an opening for continued work and maybe a phd if everything went smoothly. Half way through he revealed that this opportunity was no longer a option with the reason given being money, not my work. Around the same time I found a sidetrack and with his blessing followed that instead of the topic he originally proposed, which ended up with some interesting findings indeed. He has given general advice once every two weeks on this side-track but the findings of interest were made by me alone.

Now my master thesis is officially done and he e-mailed me that he want a meeting to talk about my report (that decides my grade), and (among other things) writes that he will present the findings from my work at a conference a few months away. This was written as a fact, and part of a longer paragraph.

I don't know how to react. If this is normal behavior in academia I don't want to seem unprofessional (or ruin my grade and chances to use him as a reference) by questioning this, but on other hand I want to get credited for my work. 

2-year edit: Got a notification that this question got a thousand views so decided to write a few words as a follow up.

My initial worried reaction to getting information about the grading and the conference in the same email was just stress and lack of experience getting the best of me. Nothing bad, such as not getting credit for my work, followed from this and I am actually a bit embarrassed that I was worried it might at the time.
You should initially react positively.  It is part of a supervisor's job to promote the student's work.  Possibly this is what the supervisor is trying to do, but the supervisor failed to explain what is going on.