Hello,
Chances of pregnancy are less in your case and the symptoms can be due to hormonal imbalance.
Hence to confirm the status of pregnancy, I suggest you to test for pregnancy by a highly sensitive pregnancy test 10 days post ovulation with a sensitive ( 20 - 25 mIU ) pregnancy test. Also then I would suggest you to get your serum HCG levels estimated since this is more specific than urine for pregnancy tests.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
It sounds like you have had some sort of dip in your hormone levels that have thrown your cycle off a bit. Stress or perimenopause can do this. If it is from stress your body should regulate itself within a couple cycles time, if you are in the onset of perimenopause you will likely continue to experience irregularity for about 10 years before you go into full blown menopause. If you are still young and these symptoms persist then see your doctor to have your hormone levels checked, especially if you are thinking about having children. If any of your symptoms get worse or are concerning to you then go see your doctor for a check up.