What Test Can Be Done For Confirming Pregnancy?

Hey doc.
I have been having symptoms that I may be pregnant I took 5 tests, the 1st one was inconclusive and I tried another 1 which came up positive and with excitement I did 2 more, the second one was positive again, 3rd one negative, I was so so sad and my friend told me to take one more and it came up positive again. I didn't get my period December and thought that it might be the cause of stress being that my place of employment was being renovated and I was the one to do all the work to get everything up and running again. 15 days ago I woke up every morning being sick and vomiting, being more tired than usual and breasts being tender and having abdomanal cramps that last no longer than 10-15 seconds. My cycle is always 21 days and it is always clock work. I counted from the day I was supposed to get my period in Dec up until I was supposed to get it in January and I was 3 days late and started to get bleeding when I went to the loo, it was light pink and did not last a whole 24 hours.
I made a doctors appointment and did a test and it came back negative, he took blood and I will hear in 3 days what the outcome will be.
Can you maybe give me any advice on this matter because I am really very confused