Can someone please help me figure out what my extreme hip/sitting bone/sacroiliac pain is coming from?

Iam going to give you my full history of this pain, and if anyone can help me narrow down what it is that would be great since no doctors seem to know. About 1 1/2 years ago i randomly developed pain in what I thought was my sciatic nerve. no injury that I know of, but Ive always been doing alot of lifting at work. I ignored it a while until one night it got so bad i couldnt walk. This was about 2 weeks after the pain started. It always was sharp and ceaseless at night, but I did pretty well during the daytime. It the more I rest, but also hurts alot when Im active. It is pretty sporatic and there are no patterns of things that irritate or alleviate pain. I have tried exercice, rest, heat, ice, and anti-inflammatory meds. I went to a spine specialist who said they saw nothing wrong with my lower spine (which is where i thought it was coming from originally)...She advised I get a sacroliac injection, which did relieve most of the pain, which means alot of the pain truly is from that joint. The pain came back in a few weeks, and has now travelled to the right side as well. The sharp night pains come and go as they please, and never show any patterns. The doctor just tells me there is nothing they can do, and that i can just get injections every so often to help with the pain. I refuse to believe that there is no way to get rid of this...and I was never even given a diagnosis!!! I cant handle this pain anymore, and now I am 3 mos pregnant and im afraid it will only get worse. My biggest issues now are that my hips always hurt, including the sides, bottom, and back of the pelvis, and where the socket is. I am just looking for at least some possible diagnoses, (ive investigated piriformis, sacroilitis, bursitis) but they all seem so similar. My pain was never tender to the touch, but now I can actually rub where the pain is. There is definitely alot at the sacroiliac joint, but newly developed is pain in my sitting bones on both sides, but none on my tailbone. If I push right under my glutes into where my femurs meet my pelvis its really tender...I really just am confused and need some answers. Sorry for such a long question but its really starting to ruin my life im only 19 and should not be feeling like some old granny who has hip problems and cant roll over in bed without yelping. Thanks so much for your help.