Which flange size fits me better? 13mm or 15 mm

Movement of nipple in Elvie stride flange...which is correct?

Elastic nipples or wrong flange size?

Sizing help please! In so much pain

Does this mean my flange is too small?

Flange sizing

big flange or little flange

Flange fit help pls!

Can someone help me with flange size? I felt like 17mm was rubbing

Is my flange size too big or too small?

Flange Fit

Help!! Flange sizing? I can’t figure it out (NSFW) nip pic