Anyone experiencing this? Am I just getting old?

I technically get pretty bad back pain when I'm PMSing, but I've BEEN feeling the pain for a while now and still no period (I have no idea when period is due, 98% sure I'm not pregnant).

My sleeping arrangement hasn't changed; could it be that? Could it be I just have back pain from ovulation, now PMS?? It just feels never ending!

I feel like an old lady and have no energy to do anything b/c of it. Any good remedies?