In the second picture you look funky because your twisting your upper body and your inside shoulder has come forward. Maybe you were over compensating for losing your balance? Check to make sure your stirrups feel even. Personally I have to have my right stirrup a half a hole shorter for me to feel and be even.
With your concerns about your arms/the bend in your elbow, try lengthening you reins a notch or two so you can bring your upper body back with out pulling in your horses mouth and getting the bend in your elbow, yet still keeping the contact.
Well there is my 3 cents....
Keep up the good work you look like you have a bright future :)