I am 48 years old. periods have been a little irregular. this month very little brown spotting for 2 days so far but no period as yet. is this cause for concern?

No. This is probably no cause for concern. At 48, as one approaches Menopause which is usually 51 - 52 years, Periods being irregular is not uncommon. Sometimes, spotting, decrease menses and even long periods without mensuration can occur. As the years of maturity and Wisdom begin, one is encouraged to enjoy ever bit of it and Mentor the Youth.

It's premature to draw any conclusions. Irregularity is expected as you approach menopause (by definition, no periods for a year) and it remains to be seen if this is just a very light period, just the beginning of a period, or a more erratic pattern that may need further evaluation. This should become more clear in the next week and you can then better decide if you need to see someone.