white/creamy colored sludge on the oil dip stick! Whats the issue?

Could be, not so good for you. apparently some coolant has got in there. Could be just loose head bolts, have your grease monkey tighten them to spec. Could be a compromized head gasket because you never checked the coolant level...now it overheats. You could clean it off, but it will re-appear as leaks don't usually heal themselves. This is bad. take a looksee at the coolant to see how much is left. top off and say a little prayer. good luck with this.

coolant level doesnt seem to be going down. Radiator was changed not so long ago though. Has a slight rattle sound, could that be loose head bolts? is this going to be the end of my truck?!?

That 'rattle' is likely to be rod bearings. It seems like you have maybe been driving a while with water in the oil and have cooked some of the bearings. How is the oil pressure? If that is low, you have done in the main bearings, too. I have a feeling you may be due for an engine. Get it to a mechanic and have it checked, including a cooling system pressure test.