A rust-red floor-length dress combines a quiet glossy surface, a diagonal shoulder line and a narrow lower outline with a rear end on the ground.
Folds around the hip and the narrower-looking line below draw a continuous shape. At ground level, the rear area spreads wider. Consider these two zones separately: the narrow visible line and the end resting on the floor. A quiet shine cannot establish stretch or room to move. Those questions need a fitting of the real garment rather than an assumption from its appearance.
Begin without a special pose. Take some of your ordinary steps and turn slowly afterwards. If you want to rearrange the lower area, note which movement prompted that wish. You can then decide whether that handling suits the evening you have planned. A different length is a practical alternative rather than a judgement about your suitability for a dress shape.
Discuss alterations using the whole lower area with an appropriate professional. Do not supply only a shoulder detail. The photograph proves neither hem allowance nor construction. Intended shoes and use matter more to that conversation than an arbitrary fixed measurement.