What should my hcg level be at 3 weeks?

Cecily • (3 baby angels👼🏻) Dakota Jace 💙 & Sophia Rose 🌹

Glow says I’m 3 weeks 5 days. I have all positive tests and my hcg is 25. Doctor said this is bc I’m early or having a miscarriage. Does anyone know if this is normal or should my levels be higher ?