When I was dealing with my sacroiliac joint pain which was pretty painful I took some Tylenol which helped with the sacroiliac joint pain.
My doctor also recommended me a Pelvic brace which also helped with my sacroiliac joint pain and it really did help.
Another option if the sacroiliac joint pain doesn't go away is to get an injection for the sacroiliac joint pain which is an anesthetic which is an anti inflammatory medicine called corticosteroid.
I had that injection and it did really help along with the pelvic brace so those are about your only options other than waiting it out.