yeah, had it happen to me once as well. didn't have to get any shots or nothin though. i was always out in the woods when i was younger. went to bed one night and my dick was real itchy, didn't think much of it. woke up in the morning and it was bigger. i was excited. i was 14. i'm lookin at it and thinkin "yeah, this is cool! that sucker is gettin thicker!"
later on that day, i'm in school and my dick has been itchy all day long. i go to take a piss, and i look at it and i'm thinkin, ok, it's gettin thicker, but only on one side....hope it evens out soon and starts to get longer as it gets thicker.
by the time i got home, i looked like Beavis in that Tainted Meat episode where his thingy itched and he couldn't stop scratching it (this was a few years before that eipsode came out). when my dad came home, i asked him if it was possible to get poison ivy dick, and he said yeah, and then laughed at me for a little bit.
sucker itched for 3 or 4 days. gettin wood was a horrible experience. painful. and i couldn't jerk it for almost a week. that was the worst part...14 and can't jerk off for a whole week. i thought i was gonna explode by the time i was able to jerk it again.