pelvic girdle pain (pdp/spd)

ivana
is anyone experiencing this or had to deal with it before? this is my first pregnancy, and the pain started when i was 12 weeks (i'm 17 now), and it's getting worse. 
i can't walk up the stairs, i can't lift my legs, turning sides in bed extremely painful (my husband, bless him, started waking up whenever i try to turn and now he helps ne by pushing me), walking is so painful and after only 10 minutes i have to sit down because i feel like my pelvis and pubic area are falling apart. 
my doc told me not to walk or stand, and even sit as little as possible, but i'm a teacher and my job is to stand and walk around the classroom all day 😔. 
i am worried because i was told that if it doesn't get better delivery could get complicated (c-section is actually not recommended, as well as epidural for natural birth because i would have to be aware of the pain because otherwise my pelvis could suffer permanent damage). 
so, any advice would be more than appreciated.