Don't worry man, it happens to everyone, I haven't smoked in a long time because of it actually, I suffer from chronic severe panic/anxiety, and I was using it to see if I could start using it medicinally, I never had smoked it and heard horror stories like most. First time I smoke it I was so scared my hands shaked while I held the pipe haha, an hour later I was not shaking and was having a wonderful time, that month was the most relaxing month I've ever had, I even went to the doctor's office and my blood pressure and heart rate had gone down to normal stats. Anyways, one night I couldn't sleep, it was like 5 am, I decided hey I'll smoke some, well I had been using a pipe and wanted to try and smoke a joint, this was very good weed, I ended up smoking a bowl (keep in mind I had only taken a hit and then let it chill for awhile and was stoned just from that,) so anyways, I smoked a bowl, then smoked 3/4 of a joint all in about 10 minuted, BAD IDEA. I was all of a sudden very relaxed, too relaxed, my breathing slowed and I was suddenly staring blankly at my lighter as I laid back in my bed, all of a sudden I lost conciousness, I awoke to what seemed like the worst panic attack I've ever had at it's very peak, and that peak lasted 2 HOURS. I went from holding my neck trying to feel my heart rate (my fiance said I was grabbing my neck so tight I almost passed out,) to puking all over my bed, and then claiming I was dying and my blood pressure was dropping, and I needed an ambulance, after about 2 hours like I said, I finally drifted off to sleep, it was by far the most horrifying experience I have ever had, and I'm sure it was because I not only smoke too much but was and still am on Klonopin for m anxiety, it was an ok mix if done in decent doses but with a high dose I wigged. Anyways, I got over it in a day or so, and now I'm trying to decide if I want to try weed again for my anxiety since I'm getting off the klonopins or Buspar for anxiety. That experience makes me never want to touch it again but before it happened it was the cure I had always looked for. Anyways, you'll be totally fine man, best of luck.