Do I have an irregular cycle?

Shayne • 🌈💙Ezra 3.17.18💙- 💗Salem 10.1.19💗
I read that a normal menstrual cycle lasts 28 days, plus or minus seven days. I get my period every month but the number of days in my cycle is always different. My cycles vary and are anywhere from 25-35 days. So one cycle was 25 days long, the next 30 days, the next 29 days, the next 35. Is that considered an irregular cycle? Am I supposed to have the same number of days in every cycle?