Confused

So my husband and I found out that we are pregnant this past week. The Dr had me take a blood test and urine test. Both positive but the blood test says that I am about 2-3 weeks pregnant. My Dr is counting from my last cycle which was in April on the 25th. So my question is which one is right? Or which one should I go by. On nurture it's going by my last cycle. This is all getting so confusing for me. Also nurture says that today I am 5weeks and 2day. Sorry if I posted in the wrong group.