Its nothing to worry about right now. They will probably regulate in few months but if you find them continuing to be irregular and they either last long time or you have long gaps between them its worth seeing your GP. People always told me they would regulate but mine never did and i ended up having nothing for six months and then I would have very heavy very painful and very long period. by the age of 16 (two years after starting i had relay only had 4 periods. I had been bleeding for two months when my mum took be to the doctor who sent me for an ultrasound and diagnosed me with PCOS. I was put on the pill which took my periods to the other extreme, if i had a period at all it would only last a couple of days, so i changed to the implant which stopped them all together, i had 4 implants over the years and never had periods on that, i got my final one out in may and have not had a period yet.