I am litely spotting between periods

Hi, for the past 3 months my period has changed its schedule. I was alway due around the 27th of each month and now I have been getting it around the 9,10, and 11th of each month. This last period which was on the 11th was normal and it lasted for around 5 days. About 4 days later I had some spotting, but that is even normal for me as I have had that happen with every period....but the difference here is that it won't stop! The spotting is not heavy at all and it is mostly a brown discharge...but it can be redish brown to lite pink as well...but nothing heavy. Even after sex I noticed some pinkish bleeding just when I thought the spotting might be over. Does this have to do with perimenopause? I am a bit scared and do not know what to think. I am 40 years old and have had 4 children...2 of which were in my late 30s. Can someone help? Thanks!