Tailbone and pelvic pain, can't walk 😞

I'm sure we're all reaching that point where everything hurts and sleep is impossible, we're so close now! The last couple of days I've gone from shooting pains in my crotch when I'm out a walk to can't lie down due to pelvic and lower back pain where my tailbone is. Baby is fully engaged, '0 space between head and exit point' is what they said at my scan on Monday. I do feel like babys head is 'there' and wondering if this is why I've got the pain i have, I've also noticed visually that the pubic area looks fat and puffy now and my husband says it was moving the other night when I was laid down and baby was active. Anyone else can't face laying down but can't get up either? And pain relief advice would also be so awesome, i normally get in bath but can't scissor my legs anymore and worried I'll get stuck if i manage to get in.