Period lasting 3 weeks

💋Nichole • Happily Married 4-4-15 💍 🎀 Baby Girl 8-28-18 Portuguese 🇵🇹
Hello, I'm writing because I am 24 years old and have no children. I have had my period now for 3 weeks and starting to think its not normal. Has anyone else had to this happen? Is this something that happens sometimes or should I go get seen?