Oil dip stick is full of oil when checking level

I did an oil change and put 4 quarts of 5w30. Initially when I checked oil after change, oil level was around hash mark area. Then when I started car and looked again. Oil level was all the way up to handle of dip stick and instead clean clear color of oil it was dark brown. Is this a sign oil is mixing with coolant?

PS: car has a hard time starting and staying on when starting.