Confused if I'm 4 weeks or 5 weeks pregnant

Felicia

My period started September 3rd and I have irregular periods. From monitoring my CM I began having EWCM on the 18th I have concluded I ovulated on the 22nd or 23rd. So would I be 4 weeks or 5 weeks pregnant? I got my first positive on October 3rd and I have very strong lines on the tests.