yes of-course the first symptom is a missed period. It is primary symptom. secondary are breast soaring, nausea,frequent urination etc.... you can do home test for pregnancy...

The earliest pregnancy symptom will likely be a missed period. Sometimes, there can be soreness of the breasts, fatigue, nausea, frequent urination, etc. Personally, I didn't experience anything other than a missed period for a week before I found out I was pregnant.

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For me my first sign was my breast being really sore worse then before a period and then my missed period and all the rest came later on. I did have some slight lower back pains on and off too tho.