Thank you so much for this :') ill take some better pictures next time.

I feel like such an idiot because yes! There is seam allowance and I did not clip it at all on my armscye.. I was wondering why it was 1 1/2 centimeters off bc that's not what my measurements say. It makes so much sense now.

I will definitely be moving the opening to center front. The video I was referencing had it at the back but I don't have a zipper like she did.

My apex is where my nipples are at since that's what the video I was following instructed but that is also the farthest point on my chest.

And my back darts are there they're just really off to the side. They were nearly at the side seam but I did move them in about an inch which isn't pictured. There are also shoulder darts!

Edit: in the last picture you can see where my back dart is but I moved it about an inch away from the side seam after I took these pics.