This is my second day w/ Z-Pak. Almost immediately after taking t...

This is my second day w/ Z-Pak. Almost immediately after taking the first dose it felt like someone had punched me in the stomach. I had been feeling so bad though for 2 weeks + I just figured it was probably just from being sick anyway. Well, I had extremely vivid nightmares that woke me up several times last night, followed by an odd feeling of dread or anxiety. I didn't realize these were common side effects and just chalked it up to something I could've possibly seen on tv earlier in the day. Today since I've been awake I've had a terrible headache, and my stomach (while I haven't used the bathroom at all) still feels like I've been punched, only the pain is more severe. I didn't think any medicine could have side effects that worked this fast, which is what let me to even looking up this medication online. I never experience side effects from medicines and have never had an allergic reaction to almost anything I've taken. This is extremely weird for me. I'm having a terrible time trying to make it through the day, and the anxiety/fear/dread just seems to get worse by the hour. So far it hasn't really taken away my symptoms for bronchitis, but i'm hoping after a couple more days i'll feel better....