Help!

I have neglected my sourdough starter (regular white all purpose flour and room temperature to cool water according to temperature of my house) for exactly one week. I finally have time to bake again so I go to my starter (I leave it out on the counter away from the oven or stove or any other hot appliances) and it has formed a top layer of dry starter in it and it smells kind of buttery. No acetone or alcohol smells, no typical sour tangyness to it. The best way to describe the smell is just like some buttery rolls (this seems odd to me). This is the first time this has happened to me so I'm not sure if I should throw my starter out or if it is still okay to use. Any help is welcome! P.S: My house temperature stays in the range of 70°-75°, there was no hooch that had formed on the starter. Still some bubbles and rivulettes in the starter, but not nearly as many as when I was using and feeding the starter on a regular basis.