I have had regular periods for 8 years now (finally), I was married a month ago and have been sexually active. I always have at least 29 days between periods but I had the oddest experience last night. When I get close to my monthly, for two days before I become exhausted, wanting to sleep, breasts sore the whole thing. When I start my period I will have brown spotting for one day then heavy bleeding with cramps.
Last night, without any signs or symptoms, I began to bleed. My period isn't due for another 9 days. I had mild cramping for a couple of hours, now it has been less than 24 hours and the bleeding has nearly stopped. I have never had anything like this happen in my life ever. I am 37 years old and am actually hoping to become pregnant with my new marriage, but what I would like to know is that if there is a chance that I could actually be pregnant with this odd occurrence?

I would say yes, there is a chance you are pregnant. Some women have a strong cramp for a couple of hours (sometimes accompanied by shattering exhaustion) when implanation occurs, and even a small amount of bleeding. The timing sounds around right for implanting.

It's not possible to know for sure until it's time to do a home pregnancy test (around the time you would expect a period) but I would make sure I'm taking my folic acid.

Yes, that is often ( in some not all women) of implantation bleeding. There is no way to know for sure at this point, but yes it does seem very possible. You will have to wait till the time for your next period and see if you miss it or not. If you miss it, then you can do a HPT>

There are many chances to get pregnant if you do sex in periods or ending of periods without protection

I found some answers here it may help you

Sex within Monthly Periods

how to get pregnant

But try to take care always in periods.