As long as you Refrigerate it. It should be fine.
Would reheat over a double boil with gently simmering water
THE NEXT DAY?
Just get eat it, it's fine.
Now, you might get some seppration depending on what recipe you used and how your cream is in there.
Leftover creamed spinach is even better the next day. I make more than I will eat so I CAN have leftovers. And I just heat it gently in a small pan--no big production.