I have been taking Tamiflu for the last 4 days but now I have an incessant dry cough that just doesnt let up. Not very productive but cant sleep well?

Doesn't seem serious. This does not appear to be serious. In fact, this is likely an expected symptom of a resolving flu-like illness. This apparently started very recently, and is your body's way of clearing mucus out of your chest. It should resolve in a few days, but if it gives you too much discomfort, some simple cough medicine should help. You could also see your Dr. if it is still an issue. Good Luck.