I would go with what works best with your body. Sometimes the better product is more expensive though... nut it's worth the difference... and make sure you get plenty of sleep... sounds like you could use a good night of sleep...
Anxiety is a frightening thing, and it has varying degrees of severity. One thing to always remember is that fear increases your anxiety which feeds your fear until you experience a panic attack. This is the dizziness and being scared you're feeling. You're obcessing over bad things happening to you and this is only fueling your anxiety. The first thing you want to do is find out if your new birth control is causing your symptoms. I feel that since the Sudafed helped with your heaches and they only lasted a week, it was indeed a sinus problem, and they can cause major headaches. So no need to worry anymore about that. It may be that you are fearful that more is wrong with you, and this is feeding your anxiety as well. You need to first find out if it's the new birth control making you nervous since it works on hormones, and if it isn't, then you need to address your anxiety and obcession of bad things happening to you. You need to talk with a therapist to determine if your anxiety has a root cause, what it is and deal with it. Sometimes this alone can stop the anxiety, sometimes medication is needed as well. But there is help, so you needn't continue to suffer with this anxiety. We're always here for support, and we've been thru this so you are talking to people who truly understand. Take care...