Why is my EBF 6 week old spitting up all of a sudden?

Why is my EBF 6 week old spitting up after every feed all of a sudden? I have tried burping her (she burps like a frat boy) and keeping her up right for 15-20 afterwards but she still spits up once or twice.

She doesn’t seem like she’s in any pain or discomfort other than her usually fussiness when passing gas. She has been a little more sleepy today but I think that’s from a growth spurt?

Any ideas? Should I contact her doctor?

*I should add I do have a forceful letdown..would that make a difference?