Period 1 day late...

I have no sign of aunt flo coming. I have been neasous for over a week, extremely tired, moody and sensitive to smells. A co-worker gave me a strawberry kiwi drink today and I couldn't drink it. Made me want to throw up. I tested last on Sunday with the first signal test. When did u get a positive test with firdt singal test?? This would be baby #2. Would it be possible that the hcg is just taking longer to show up in my urine?? Thanks in advance!!