my snake has a reddish-purplish line goin down its underside clos to the tail.is this a problem?my temps are 88 through the day and 80 4 night.he is a newborn and has never shed.he ate a week ago.Please help.

here is a pic



I I I
I I I
I I I
I______________ I____ __________ I
This is the tail.The I's in the middle are the line i am talkin about