bubblycrazy

Ok... Starting off here. I'm not pro vocal coach. And if this suggestion sucks, throw it away.
 
I'm hesitant to touch that voice that I admire in any way. Having you here is like having a classic radio station. But I have a suspicion both issues might be related to your vocal style on both parts. Breathier sounds in general dry the throat quicker by blowing more 'air' across the area. Think about other wet surfaces, how blowing air can dry them a bit. The voice is similar, breathier voices are in generally more tiring and drying.
 
A breathier vocal style can also lower the break point where you might transition to a falsetto ish (yes women have it too!) due to excess pressure from breath and not enough closure in the vocal folds. You mentioned in another thread envying another singer's high notes, and as far as I'm aware the voice will hit a wall at some point where range is limited due to breathiness for these reasons. So when we include breathy qualities, we always sacrifice some range in favor of style.
 
So my first suggestion is to please don't stop singing with the sexy, sultry, breathy tone, (pretty please?) and abandon it in favor of squealing high notes once you learn the trick. I really like your voice. But maybe look into experimenting with less breathy phonations that you might be able to work into your style as well, and learn how to control the amount of air a bit in your voice? 
 
The most efficient exercise I know of for quickly finding a less breathy phonation is to say a vowel very very very very quickly. Like as briefly as you possibly can. 'O' instead of 'oh.' Turbo quick, quicker than you think you can do. Most people will automatically make a less breathy sound. The most important thing is you need to make sure the phonation still feels relaxed and comfortable as you can push the voice too far and 'press' the phonation. You want a comfortable tone that works well for you.
 
Anyway, from a really short vowel you can gradually extend that sound out. If you do that onset exercise, you might hear a little tic, (glottal action, you can hear this in like country and pop singers sometimes when they onset their vowels) which in the long term is probably not desirable for your style. So you'll likely want to include an invisible, very tiny H (so small as to be almost not there) to soften and cushion that sound.
 
Basically, that's the best I can do for you as 'random singing guy.' You should probably get a great teacher if you don't already have one since you are starting a professional journey, a professional to keep you healthy and spot check you would be really valuable. I'm not gonna be a pro and I'm fairly poor, so I'm gonna sing as an amateur as carefully as I can. I make sure I never go hoarse and my goal is to have improvement in my voice every time I sing.
 
But you're already going pro with gigs! So you need to take extra care of your pro instrument. And thanks for sharing, I love it, including the crack. They are endearing whether you like them or not.