Confused

I'm on my 4th day of being late for my period, I have taken several hpt which have all come back negative I have also had a blood test which all so has come back negative! Been having severe cramps, nausea, sore boobs severe back ache upset tummy & headaches for the past 2 weeks I'm booked in for a scan to check my ovaries (this was booked before late period) as I had bleeding a few weeks ago! I'm in a panic mode as to what is happening :( just want answers now! Has anyone else been through or going through this now? thanks in advance xx