15 dpo possible faint positives , are my s&s normal?

Today is 15 dpo & woke up with terrible lower back pain , also my boobs had been heavy and painful in the am when I woke but now are just slightly sore idk if this should concern me, I've been experiencing twinges where my uterus is intermittently this morning felt a little painful more like discomfort along with the back pain, should I be worried? below are my tests by dpo the one with no title was 12 dpo, any thoughts would be good .