confused about dates!!

[scaredbuthappy]

Can i just ask a silly question.
Do they class the first day of your last period as day 1 of pregnancy or is the day you actually concieve.
Im supposed to go to my clinic at week 8 but is that week 8 from my period or week 8 from when we likely concieved. Because at the moment i could either be 5 weeks pregnant (1st day of last period) or 3 weeks pregnant (day it was actually concieved).
Im confused because technically im not actually 5 weeks pregnant because the 1st day of my last period there would of physically been no egg to fertilize! The only time roughly my egg would of come out would of been 2 weeks later hence why i should only be 3 weeks pregnant???
So am i 5 weeks or 3 weeks? And would i of had morning sickness by now if im 5 weeks? Thanyou sorry for so many questions.

 

[Sherlock]

First day of last period is where they work from.

Congratulations

 

[Kylie1007]

Yeah 1st day of last period so you might be 5 weeks pregnant but your baby is 3 weeks old. That's something to bear in mind when you're looking at fetal development on the internet as some people do it in terms of age of baby and others do it in terms of pregnancy.