Change in life (as you have gone with marriage) may have some changes in our body. Especially females may face such issues frequently due to their complex hormonal system. 6 day delay is an insignificant time to diagnose something. I would suggest not to worry. Secondly, this slight pain
and change in color in the breast can also be seen in connection with slight hormonal disturbance. Again, it is not worth worrying. I would recommend to observe the same symptoms for another three months, if it continues you can contact me for the same.