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Frequency of urine;nausea
;sick feeing;giddiness;breast tenderness are few commonly seen symptoms of pregnancy
.But the first symptom from which you should suspect pregnancy is a Missed/delayed period.The best thing you can do if you have missed period is to get a urine pregnancy test done with morning first sample of urine.;if the test is positive then you are pregnant.
Hope this answer is helpful to you.