Late ovulation?


i got tested today hcg is 33

i have no clue how far along i am as my cycles are irregular sometimes 28 sometimes 32 i also dont get the whole dpo thing? the dr said shes gonna assume im 10dpo but i was thinking im due for my period friday which would be 30 days to be faire i dont remember the exact day my period started but i think it was the 21st of April with bleeding for 6 days anyways she said progesterone was 26 which us good since with my son it was 19 and dropped im going back in 2 days to be checked again but should i just give up on this pregnancy 33 seems awfully low! :( tia.