Bali bra too tight

I have been wearing the same size bra for about thirty years so I thought it safe to order the Bali bra size 34D. I was shocked at how constricting the sides were while the cup size fit. Let me explain that I am a very petite woman. Most women as small boned as me don't wear a 34D! So that is why I was shocked at how tight the bra is. I purchased a two inch extender at Walmart which helped and I am planning to purchase a second two inch extender. No point in feeling like Scarlett O'Hara. I recently heard that wearing bras can cause breast cancer because they constrict the lymph glands in the breast. Being a three year breast cancer survivor I now feel good about wearing my old bras that are loose. I have bought Bali bras in department stores in the past and they have been great but the one I purchased on amazon.com did not fit.