I've been on 50g of sertraline for around 3 years with good results.
Over the past 6 months my anxiety has increased and came to a head while I was on holiday on Spain (typical) :(

2 weeks ago my GP advised me to increase the dose to 100mg.
The First week was fine. I'm just coming into my 3rd week and I feel terrible.
Flu like symptoms, head pressure, dizziness, no appetite, Nausea, waking in the night in complete panic. Strange dreams..

Do you think this could be side effects from the drug increase or the anxiety getting the better of me?

I'm now thinking I should change doses or brave the next few weeks in the hope of an improvement.