Irregular periods

So I got scared two days ago because ever since I was 13 my period stop coming regularly ever month and well this month scared me because It was about to be three months that I didn't get it but I did two days ago and I feel like it comes worst every time,really bad cramps, back pains and stuff. Is that normal for a irregular period to be like that. Can I get some advice on what to do or why it's like that.