FTM lower back pain

So I know the answer probably is this is normal and I knew I would be limited but I’m only 25 weeks and I get what I assume is sciatic pain in my lower back that makes me stiff. The problem is that the pain is so bad that every few days I can’t walk and need assistance. My leg gives out from the pain. Stretching and heat help a tiny bit but not enough. Is this normal? How do people get things done? It’s just pain when I try to move so I don’t think it’s contractions or anything.