Hey,
I noticed this pain a couple of weeks ago at around 32 weeks and came across some articles about SPD online so went to see my doctor and he confirmed that it was indeed spd, he gave me some paracetamol and some information on certain do's and dont's etc and sent me on my way.
Some things that help me that you might find helpful, i started sleeping with a pillow inbetween my legs and this really helped me, sometimes i will wake up during the night needing the toilet which is when it can be most painful for me so i started sitting on the edge of the bed for a couple of minutes and rotating my hips lightly before getting up. Taking smaller steps when walking can help as well i find. obvious ones like dont cross your legs and a midwife suggested keeping your knees together when sitting and getting out of the car etc these tips also help.
Zoe x