I could experience vomiting since the last contact with my husband, is it posible to feel the symthoms of being pregnant in the first day?

You don't actually conceive the day you have sex. But you could have conceived from a time before that.

I don't think "morning sickness" actually starts until around 6 weeks after conception so your vomiting probably is not from that.

No, you wouldn't have morning sickness that soon. You probably just have a flu bug or upset stomach. Not that I'm saying you aren't pregnant, but the vomiting probably isn't related.

No, you don't experience any symptoms of pregnancy within 24 hours of intercourse. The reason is that it actually takes about 3 days for the sperm to travel up the vagina, through the uterus and up into the fallopian tube where the egg is then fertilized.

You probably have a stomach flu. It's been going around heavily where I live.