18 weeks 4days and drained

Has anyone else had a back ache and feel crampy in their back almost half way through pregnancy? For the last 2 days Ive felt drained. Back aches, back cramps, nauseous and just all over not feeling it. Also I think he’s kicking my pelvic bones. Sometimes it hurts in the front but like on my bones on the sides. I can feel his kicks and have a Doppler he has a strong 144-145 heartbeat. Check it daily. He’s always down by my c-section scar. Should I call my OB? Don’t have a appointment until October 5th. 22 week anatomy scan appointment. This is my second child had a c-section with my first son.