Hi E., I am 36, had girl #4 just over a year ago (first and only c-section, then had my tubes tied). I just stopped nursing a little over 1 1/2 months ago and am still 25 pounds over my pre-pregnancy weight (gained over 65 lbs). My body has been through alot in the last 2 years (well 17 years) and is starting to get somewhat back to normal.
I have experienced HEAVY periods (for years) and light (normal) periods. They have changed with each pregnancy, going from 10 days heavy every 3 months to 5 day light period every 4 weeks. I did have some spotting and a couple times had a period 2 weeks apart (after this last child). But this is normal for me (change in cycle). So I was not concerned (because there was not extreme pain/discomfort or that gut instinct that something was wrong). From my experience, your body goes through so many changes. Especially when something new/different happens (birth, tubal ligation, etc). Every women's body is different and they have all experienced different things (normal for some, adnormal for others). Be cautious when taking advice. It is comforting to know that others have gone through the same thing and things turned out fine (which is good to know). But, when others start giving you a diagnosis based on what they experienced, this could put you more into a panic state than you would rather be in. I know I have freaked out when given advice and find out later that there is nothing to be worried about.
Anyhow, my advice to you is that if you are in anyway concerned, then see your doctor. You know your body better than anyone else. I would rather you see your doctor, have it documented that you've come in concerned, then have the Dr. tell you "Don't worry, this is normal.", instead of you doing nothing and finding out later, you should have gone in. You will be be more at ease, especially knowing that your doctor is aware of your concern, is not concerned and can monitor things if necessary. It's better to be safe than sorry. It's better for your doctor to be awar of what your going through, even if it turns out to be nothing. If anything, I think you will feel better if you go.
Good luck to you and God bless you and your family.