First pointe shoes- fit question

Hello everyone! I was fitted for my first pair of pointe shoes recently and got the brand Mirella in size 7xx. Now, I think that the shoes might be too long and I expressed it to my fitter at the time of the fitting but he assured me that this was the right size for me. The fabric at the heel seems to bunch up significantly when I go en pointe and I don’t really feel supported, if anything I am nervous because I can feel the shoe slipping off the back of my foot. Also, these shoes do not have elastic drawstrings and instead have thread like drawstrings that are really hard to adjust and keep in place without them constricting the blood flow to my feet. I decided to try on size 6.5xx to compare them and I feel like I get more support and stability with the 6.5 but even when I’m just standing flat I can feel my toes slightly pressing against the bottom of the box, does that mean they’re too small? Are the size 7 the right size for me? Here is a video of the size 7 shoes that hopefully shows my main concerns, I will also add pictures of me in both sizes in the comments. Please let me know what y’all think and thank you for any help, advice, or suggestions!