Welcome to BW
We don't really know what causes it but we know that its pretty normal at this age and she will likely grow out of it.
How to get through the evenings until she grows out of it:
- lots of cuddles
- let her sleep wherever she will (if that's on you or whatever, that's fine) if she will
- keep things low key - this is often the time when father returns home and the house is busy with dinner prep, playing fun things with baby, eating, etc. That's fun for adults but really overstimulating for a baby, so keeping the general noise down and just doing cuddles rather than games that make her scream and laugh.
- know that if you've met her physical needs - ie. she is fed, clean, warm enough, etc. she's probably needing cuddles and you cannot spoil her by providing those.
Hugs xx its hard to hear your new baby cry, sounds like you are doing a great job with her