Thinking I am pregnant again

Tahama

I had my first period after delivery in august, all these months it was regular last month, my periods were different, very light than usual and no periods this month, now I am worried if i am pregnant again, i did a pregnancy test yesterday but it was negative but with my first baby I got no positive test in strips and had to finally go for blood test in which i got to know I am pregnant, now I am super confused what to do?

Should I opt for blood test