tired arms- only low octave

[TonyMex]

I Friends:
I am new in a flute use. In old days I had played the Sax.
When practique, My arms will tired. I cant mantain the flute in horizontal line a long time.
I can play the first octave. But when I get the F in second octave I loose completly the control.
I am practique in the mirror many time because I think than the error is in the embouchure-
This is normal.... Haw many time is necesary to achieve all notes?
Thanks and good day.
Tony

[fliccolo257]

it could be that you just arent used to it...sax and flute have different positions as one can tell but if you really arent getting use to it, try doing some arm excersizes to build up some endurance for that and always practice standing up...because it'll help your breath support too and youll find it much more rewarding when you have to play in front of others because youll have a better posture whether sitting or standing and your position will be more than likely correct...hope it works out