Hi I am 13 weeks pregnant with my 3rd child and have been really sick I already lost 10 pounds never had sickness with the other ones but my clothes are getting tighter do you think the baby is growing right?

Only a doctor could tell you that, you should go see one.

I agree, you should go see a doctor soon

Weight loss is common during the first trimester, especially if you have morning sickness. If your doctor is not concerned at this point, neither should you be. Just make your concerns known to your doctor and s/he should be able to allay your fears.

hi i am 13 weeks pregnant with my 3rd child and have been really sick i already lost 10 pounds never had sickness with the other ones but my clothes are getting tighter do u think the baby is growing right?
Think it could be twins?

I had a ultra sound at six weeks and they said only one

So have you seen the doctor recently? If not, then you should bring up your concerns, right? We can not really help you here except advice you that if you have concerns, then it is best to talk to the doctor.

Best wishes.