I'm actually dealing with my own bobbin issue myself right now, do be sure to take a moment and make sure your bobbin is correct for your machine. I bought a set of 50 Class 15's that would normally fit my machine, but discovered the hard way that once I got the bobbin wound and then put into my machine, there's something wrong with the bobbin itself. It didn't feed the thread through smoothly like others that I've had and it caused bird's nesting, a lot of broken bobbin threads and was just a general pain. Once I put one of my older ones in that I knew would fit, I didn't have that problem again.
Now that I got that off of my mind (lol), there's a way to adjust the tension when you wind a bobbin, usually a screw, mine I just move either to the left or the right and it'll feed it correctly.