Short and lighter period?

For the past months I've had 37 days cycle. But for this month my period was a week early. Not just early, but also lighter and shorter than the usual. I usually bleed 4 or 5 days. Starting heavy on the 1st and 2nd day, to light then spotting on the 5th day. My early period this month started by spotting light brown in the evening, next day light flow in the morning, medium then stopped for hours, light again til the next day. Then it just stopped. To sum it up, it only took 2 days. My man and I had fun days after my period last month and didn't bother pulling out one time.

It just felt really strange and I feel very different. Also felt a pinching type of cramping which is not the usual symptom for my period. Might test on the day my actual period should have come.

This happened 2 days ago. For now, I'm dealing with backaches and still cramp a little but no more bleeding. Any opinion?