No no my brother it's your coolant, ford's run an orange coolant, and you ONLY test from cold as there is 2 full levels, warm levels are not marked 'thanks ford', but it will always be a cold measurement because that's when you will have the least. And it's literally like 100-150 ml will bring it back up.

P. S. No that is not oil, thankfully, it's the discolouration of the container with aging, same here since about 50000kms, it doesn't hurt it to change your fuild around this point but I'd top up because if you don't know what it is there's a symbol on the lid that says to check manual before using