I started taking wellbutrin sr 150 mg about a week ago. I did ok...

I started taking wellbutrin sr 150 mg about a week ago. I did okay on it, but my depression wasn't better. My doctor increased my dosage to 300 mg a day (150 mg in am, 150 mg in pm). Since then, I have had 1 panic attack, and I feel like I can't stop moving around. My heart also started to "flutter" a little bit last night. I'm also taking xanax for anxiety, and I admit I've taken more of it the last few days to deal with the anxiety. I think I'm going to go back down to the 150 mg once a day for a while, because this anxiety is killing me.