BACK PAIN?!? 5 DPO

I’m on CD 16 so I’m in the TWW. I’m 42 and TTC my fourth (first with my husband, high school sweetheart). My older three are 17, 16, 10.

I honestly don’t remember exactly how I felt in the TWW with them but the last two days my lower back has been in such excruciating pain! I’ve done nothing different and nothing changed.

I either need a new mattress all of a sudden out of the blue or maybe it’s an early symptom? Wishful thinking? My God it hurts bad.