Natural Cycles App and lower back pain

First few months lots of ‘red’ days (no unprotected sex days). Coming off the pill was a personal choice and brought back lots of issues i.e needing prescription pain medication. However, my sex drive and mental health have significantly improved and impacted on my relationship. I’ve used natural cycles for 2 years religiously and no problems or pregnancy.

You have to take your temperature and do a ovulation test ( wee sample ) both in the morning then you add all in the app and it tells you if is a red day ( which you have to use another contraceptive method ) o green then you can have sex without contraception because when you have a green day you are not meant to get pregnant . I think if you want to get pregnant go for this app ! but as contraception is not very good as you hardly ever get green days and when you get them ( very rare ) you feel you can still getting pregnant also boyfriends / partners find so difficult to trust the app which it makes it even more difficult for the woman . As an app works very well and is interesting to know when do you ovulate or if you don't ovulate or if you ovulate twice but as contraception needs improvement

Was on the combined pill but changed a couple of months ago to natural cycles. Mood generally better, sex drive much better, skin slightly worse, periods & cramps much the same (bad, but that’s just me and my womb)