Can you have tightenings/cramping in your back as well as your stomach?in pregnancy and or labour?39+3weeks today?

Could I be in Early labour ? Was feeling ok this morning but then all of a sudden I come over all tierd and my back started hurting really heavy pain but I had been hoovering before that then I sat down and had been sitting for quite a while trying to chill then I had like this funny sensation in my back like a wave of pain but felt more like a tightening and a crampy feeling like you get in your stomach when you have braxton hicks / contractions and since then too I have been having stomach tightenings and pressure down below , could this just be my body getting ready ? Or could it be the start of labour ?