Back pain send help

So I’m 27 weeks almost 28 and I’ve been lucky enough to not really have any back pain so far only one time really. Today I woke up with a little back pain and it went away at work. I work as a preschool teacher so I’m bending over and moving all day. Around 3:00 my lower back started hurting and it really hasn’t stopped. Anyone have any tricks or anything that can help. *** it’s not so painful I had to stop working and I’m having no bleeding or change in discharge or anything