It seems that you have a hormonal imbalance. This can cause you to have irregular periods
and symptoms like that. With hormonal deficiency
any symptoms are possible. I also recommend that you get tested for PCOD
which is present in about 10 % of females. Once you get tested, it should help you greatly to reduce your problem.
Weight gain can also be one problem in your case. If you have acidity, it also presents sometimes with back pain
. I hope this helps.