Oh bless your heart, I so feel your pain.
SPD is something that I had never heard of until I got it with DS at 18 weeks. I was put on crutches straight away and told to rest
which wasn't possible as I was still working and had a young DD at the time.
I was told to take paracetamol and have lots of warm baths and all would be fine. Not so. Make sure your MW and GP are badgered all of the time if you're in pain. You can use a TENS and you can take co-codamol as long as your GP/MW knows about both as a TENS can trigger labour which you may want some nights but not yet sweetheart. :)
I had hydrotherapy twice a week, which helped me massively, I had physio at least once a week, and also told to sleep with plenty of pillows and to lie on one side, not on my back.
If you search the site, you'll find lots and lots of SPD threads because no-one knows what it is until they get it. It's horrific. I'm so sorry that you are suffering.
I would (and did) -
a) - invest in a well fitted maternity belt, thick and covers the bottom and the surround of your bump.
b) - take paracetamol, use a TENS and ask for co-codamol. Try to use breathing techniques for for the pain.
c) - DO NOT LIFT OR PUSH ANYTHING YOU DON'T HAVE TO. Even opening a heavy door will hurt.
d) - if you drive, get a swivel seat LIKE THIS you can get them cheaper, Aldi have them in now, DH got me a new one last night for £10.00
e) - Make sure EVERYONE knows you have SPD. You need to give birth on your side if at all and I was told to have NO epidural
if you can bear it because them moving your legs about or any pulling, can pull the pelvis apart more, or so I was told but it's up to you. I managed to birth on my side with no pain relief just G&A for a while and then gave up because I just wanted it over with.
f) - Try to see a physio who specialises in this sort of treatment, an internal exam may help too so that the can tell you how and where the SPD is affecting you. GP or MW can advise on that. Be careful who you see, don't let them pull you about AT ALL! Make sure that they lower the bed for you to get on and help you get your legs up, ask for pillows for support whilst in there. If they offer you crutches, take them! I was on them from 20 weeks and induced at 39 weeks.
g) - everything that all other wonderfully supportive posters have said to you so far up thread ^! SPD is a nasty disability and it will not just go away once baby arrives, but then again, it may. As others have said, do not let it go. I ended up having x-rays and MRIs which showed that I have various other health issues but without the initial and still lingering SPD, I wouldn't have found out.
DS is 4 in 2 days and I still have pain, especially when it's cold and damp.
Take good care of yourself and good luck with it all xxxxx
(PS - sorry for any typos, DS is not a sleeper!
)