When was your last period?
How bad is the cramping?
It is possible for you to be pregnant. The fact that you are cramping and spotting is a concern. Since this is about four, almost five weeks after your last period, could also be your menses is about to start.
I would call your physician and ask for a pregnancy test to be done by a blood draw. It is the only way to know for sure. You can have the office fax an order to a place convenient for you and have it done as an outpatient (such as a hospital or outpatient lab). Explain to them the symptoms you are having so that they can get a stat run on it.
If your pregnancy test is positive, you will want to contact your physician right away for further instructions.
I hope this was of help to you. Please let me know ifyou have any further quesitons or concerns.