It's normal for some calamari to be slightly pink in color.
However if your calamari has really brighter pink in color then it could be bad and should not be eaten.
When calamari turns more pink it means the calamari is going bad and if it's slightly pink the calamari is safe to eat but overly pink it's likely bad.
Thawed or fresh calamari should be mostly ivory colored and moist and shiny.
Yellow or purple or pink flesh indicates deterioration of the calamari.
If in doubt just throw the calamari out to avoid getting sick.
Although if the calamari has been frozen and it's not too pink it could be okay to eat.
If I'm ever in doubt about some food being bad I just throw it out and don't eat it because it's not worth getting sick over.