Nipple Shields?!?

Cheyenne • I an 27 and I have a 3 year old boy, 6 year old boy, a 7 year old little girl, and 16 month old little girl
Can anyone who has used these tell me if they worked and if they liked them? Right now I am going to try one with my 4 day old because I think I have overactive letdown and its choking her and because my nipples hurt and burn so bad because of her stopping and starting that it makes me want to cry. I am seeing a lactation consultant tomorrow so I will also ask her but I wanted to try to get some relief between now and then. If anyone has any tips or tricks to using these or breastfeeding in general I would like to know.