i can’t tell if my new peep toe pumps are too tight?

i just bought my first pair of high heels 2 days back, they are jessica simpson, 3.5 inch heel and .5 inch platform, red patent leather. i got them in a size 6, and jessica simpson runs a little large in size. but when i put them on it seems as they fit perfectly, but then i start walking on them and i feel tightness on the area where my toes are, and a bit looseness on the heel part. the balls of my feet also start to hurt very quickly, this i'm not sure has to do with the fact that these are my first pair of heels and i have not gotten used to the pain of wearing high heels, or that the shoes are too tight. i tried a six and a half and there is a bit too much room in the heel area (back of the shoe). and when i would walk the back would slip off a bit. so i chose the 6.

any tips, suggestions, or thoughts on my situation? do you think they are too tight or is it just that i am a beginner

SOFFT Peep-Toe 7 M Patent Leather T-Strap Pumps Heels