A tens machine worked for me, didn't put it on too high just for 15mins at a time. And I used heat and ice packs throughout the day. I've now a 9month old and I've found out it's long term back problem so it's struggling with him being so active now z
I second a tens machine, you can also use it during labour too so win win x
Chiropractor worked for me - helps to unlock where the nerve is trapped and if there’s any other tightness or aches for a changing pregnant body, it helps to ease it.