9 weeks can be a pretty normal time for the first trimester symptoms to ease up (its different for everyone! My morning sickness didnt until around 28 weeks LOL)
TBH I never even really had breast tenderness that was all that noticeable.
Any symptom can come and go without issues... but really with the timing of this I would be even less concerned because you are nearing what is the most symptom-free part of pregnancy for most women. Before long you will start showing, feel kicks and then eventually have the heavy-pregnant symptoms... but for now, maybe you should be looking for symptoms you wouldnt normally think of?
Increased energy? Oily skin or clearer-than normal skin? Faster or slower than normal hair growth? Cravings?
Not every pregnancy symptom has to make us miserable... some lucky women get clear skin, gorgeous hair and very little body hair during pregnancy.
Lucky... lucky lucky women.

lol