twins?

Kelly
Hey so i found out I'm pregnant over a week ago 😀 super happy, I'm about 5-6 weeks,
Basically my partner has got it in his head I'm having twins lol 
They run on his side of the family one set of twins they sadly passed away.
What are the symptoms of a twin pregnancy?
I hardly sleep, and feel sick on a morning but I thought morning sickness doesn't start until about the 8th week?
Any advice would be great ful
Thank you ❤