Me and my husband had unoprotected sex one week ago and about 2 days ago I started to feel sick to my stomach and very crampy what could this mean'?

Most likely you have a virus.

It could mean anything. I get cramps and sick to my stomach if I eat too much chinese food. It is far too early to be experiencing any signs of pregnancy. Most likely you are close to a period, you have indegestion, or as J_9 has said, a virus..