Yowza! I haven't had any period like cramps since week 4 and then cramps turned to round ligament pain which was shooting pains. Those types of cramps were fine by me because they at least didn't feel like my period was coming. In the past 24 hours at 8wks and 4 days I'm feeling some period like cramps that are also cramping my legs as well. It comes and goes, but it's consistent whereas usually my symptoms show up for a short time and then go away until a few days later. They aren't super intense, I'd say somewhere between mild and moderate and haven't progressively worsened.
I read somewhere in a few places online that you can have some period like cramps at the time that your period would normally be due and sure enough, I looked at the calendar and my period would've shown up this past weekend. I don't really understand why that would be because I obviously didn't ovulate this past month since I'm preggo so I don't know what would trigger my body to think it should be getting a period.
Anyone else know anything? I'm just so nervous that it's going to get worse and leading to something bad....

Re: Period Like Cramps at 8 Weeks
I don't have any amazing explanation, but I can say that this has been happening to me occasionally and everything is a-OK!
I had the very same type of cramps at 8 weeks (right when my period would have been due) and was really concerned as well. I did some online searching for answers like you did and found the same info. I had my first u/s at 8w6d and all was fine so that was a huge relief after having had those cramps.
Try not to stress about it too much. Hopefully your cramps go away soon and you're back to feeling (somewhat) like yourself!
BFP #1 09/02/11 M/C 09/12/11 8w6days
BFP #2 07/18/12 Baby S born on his EDD 03/23/13
SS - age 12...SD - age 8...DS - 13 mos.
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It's a girl!
I had this.. I asked Dr. they said could be two things. IF NOT BLEEDING - Then placenta growing or bowels. She said most likely its the bowels though. I asked if she was serious and she laughed and said yes.
I had no idea that pain from my bowels contracting would feel like that.