You can have mild to moderate cramping (similar to menstural cycle cramping), backache, headache, fatigue, nausea, vomiting, fluctuations in appetite, constipation, diarrhea, mood swings, breast tenderness
and/or frequent urination
. However you can also experience none of this. If you don't, it doesn't mean the pregnancy is doomed to fail. Same as having these symptoms - it doesn't mean all is well. How a female feels while pregnant will vary from female to female and pregnancy to pregnancy.