Is it possible to only have a cycle of spotting?

So a little back story. I have irregular periods. My last Period was Feb 2nd-7th. I usually have what I consider medium flow for 2 I'll get 1 days of heavy and 2 days of light. This is the same everytime I have a Period. I went to the doctors May 20th for this issue of irregular periods and non ovulatory cycles. Well turns out everything is normal down there but I did find out I was pre-diabetic which was causing my cycles to go crazy and not ovulate. I was also screened for PCOS and after a US they found that I am clear which is awesome. Now fast forward to the 24th I have some light spotting. It was red the 1st day. The spotting lasted 4 days and only showed up on a pad sometimes. It went to brown by day 2. No spotting day 5 and 6. But more brown spotting slightly heavier day 7 and 8. Now no more spotting. I should also note I tested 2x a day for 40 days and did not get a peak so I know I did not ovulate this cycle.

So now for the millions of questions I have...

1. Is it possible to have a cycle of just light spotting.

2. Could it be old blood from the pap/US on the 20th?

3. Isn't TTCing stressful sometimes lol