I am 30 years old and have never had a regular period. Sometimes 3 months betwrn. They were always 5 to 7 days long and I never had a lot of pain or excessive bleeding. I have currently been bleeding for 18 days the first 5 normal and the remainder very light. LNo pain but I am concerned

I'd set an appointment and see your gyn about it. There are a number of reasons for irregular bleeding, some minor, others you would need further looking into.