Cannabis smoke targets different pathways in the lungs compared to tobacco smoke and is less damaging to the lungs because of it.
In terms of actually smoking blunts or bongs, it's a bigger high (your smoking more weed....) but it is harsher on the throat. I myself find it difficult smoking more than half a blunt wrap on my own, so if your smoking by yourself, then don't smoke full on blunts (with blunt wraps) on your own. You sound a novice to smoking (no offence mate) so it is very possible you could whitey, which isn't a pleasant experience. If your having a stoner sesh, then remember that blunts use up a lot of weed.