So nervous! BFP after 4 years

I got a BFP last Monday after suffering a loss in 2015. Had my blood drawn to confirm and my HCG levels were 24. Went back 48 hours later and my levels rose to 178. I was experiencing symptoms...cramping, tender/swollen breast but they seem to have disappeared. We’ve been trying since our loss in 2015. I’m so nervous and hoping it’s not happening again. I am scheduled to see the doctor on Thursday. Anyone experience slow climbing levels and had a successful pregnancy?