Pacifier Size/Brand Recommendation

Emily
My son is now 8weeks old and currently uses the Nuk pacifiers and we have the newborn ones for him and they seem to be leaving marks on his cheeks because I'm thinking they are too small but when I tried to give him the smoothie pacifier he did not seem to like it as much but the other ones are making imprints on his little cheeks. Any pacifier suggestions or suggestions on this matter. 
Thanks!