Symptoms but not pregnant??

Hi gang... first time posting so hoping you can help!!

I have sex on the regular and am on the pill, but over the past weeks/ months have been experiences tender breasts and puffy/ swollen nipples, back ache and have been having an up and down libido (Which is slowly driving my boyfriends nuts!). I haven’t had a period since October 2018 but they’re pretty irregular so didn’t think too much of it.

I did a pregnancy test on Saturday (The 19th) which was negative.... any tips or advice on....

A) What is wrong with me? (I’ve got a doctors appointment in a couple of weeks but GP has a long waiting list!).

B) What can help get rid of this pain (Especially in my boobs as I can’t wear a bra or touch them as they’re so sensitive!).

Thanks! 😘😘🥰