Heading into surgery

I came in to the hospital Tuesday night with ANOTHER kidney stone! (I was here last week with one) got admitted, & told I was going to have surgery to have a stent placed to try and help pass the stone baca use if it's size, it will give me more issues if I don't have this procedure. I'm so worried about the anistesia & just surgery I general. Especially 30 weeks pregnant! I've read that these stents are extremely uncomfortable. I've never even been hospitalized, one ever in my life. Only when I gave birth to my daughter. This is so scarry for me.