Spd and tailbone pain, or do I just have a big baby?

My spd is so bad I literally need a wheel chair right now 😭😭 I was cleaning my house yesterday and

Since then it’s been so bad I thought it would get better if I rest and nope! Woke up still feeling pain.

I’m 36 weeks pregnant with my 5th and my belly is so big bigger than my other pregnancies I can’t even reach to wipe when I pee, i can’t wash the dishes either or sometimes even cook because my belly is in the way of everything. I do have GD this pregnancy and I’m worried maybe my baby is too big all my other kids were 6-7 pounds. My ultrasound last week at 35 weeks showed baby measured about 7 pounds and I know it could be off it’s just an estimate but I’ve never been in this much pain before 😢 my lower body is giving up on me