Morning sickness can be different for everyone, but for me it was like being seasick constantly...I remember b/c I am now 27 weeks and STILL suffering from morning sickness lol!
You can begin to feel symptoms as soon at 10-14 days after intercourse the results in fertilization of an egg. Morning sickness is usually the feeling like you have to throw up, the unsettled stomach feeling. Many women actually DO throw up while others just feel queasy and can't eat. If it has been an entire month since you last had intercourse it has been plenty long enough for you to be able to take a HPT.