Blueberry Muffins

This recipe calls for fresh blueberries which i did use but i don't know if i put in too many blueberries or that the oven temperature was not hot enough or that i over-stirred the batter? I know muffin batter has to be lumpy but do i leave the lumps like that with the flour still in bubbles or what? I don't really know. Anyway, the muffins end up tasting ok but i am just disappointed that it didn't raise up very much and that it doesn't look that the ones in Starbucks..hahahahaha..



I don't really know also why the inside of the muffin is so soft - maybe i put too many blueberries?