Helo Needed!

I am 5 days late. I have taken 5 tests. 4 which showd up positve even though the line was very very lite. 5th one came out negative. I have never had this happen to me. I have had 3 children and with each of those my lines were there and I knew I was pregnant. I don't really know if I should just wait or try to get in to have blood work done?