The first thing I want to stress is you should really consider teaching her bite inhibition first. Teach your dog how to bite, she's an Akita, and bite inhibition may save some heartache in the future by working on it now.
If I had to guess, the problem you're having is your allowing her to get to a high level of excitement. Before she gets to a level 9/10 excitement, relax her at a level 5/6... Once she gets to a high level of excitement it will be very hard to redirect her to calm down. She is young so she has a lot of time to learn to control her impulse and you'll need to be on your A game for quite awhile until she starts maturing. So, again, don't allow her to get to a level 9/10 unless you are 100% in control.
Next, you need to be sure you give her the right opportunities in the right setting to work her out mentally & physically. Are you doing basic house training/ground rules with her? Is she getting enough exercise so she has an outlet for her energy? Playing with her? Ect...
As for getting her over her fear of being outdoors alone; go with her. Play with her outside. Get her mind off being scared so that she starts exploring outdoors while your around her. Work/train with her outside. Build her confidence outdoors so that she can retain the confidence when you're not around. Then she'll stop focusing on being scared and get accustomed to her surroundings.
Here are 2 other posts that you should read on here:
Advice needed please :)
Puppy Problems!
There's a lot of info on biting and over excitement on this forum. You;ll just need to search around. Good luck. Hope to see some pics of your girl too!!!