Use lots of lube. It might take you a while for your body to get used to it. If you are chaffed inside, you may need a couple of days to heal in between. If you notice any blood discharge (could be just slightly pink when you wipe), you are probably chaffed. That in itself is nothing to worry about, but it shouldn't continue. As I mentioned, use lots of lube - stop in the middle to lube up if you need to. Also, your BF's technique may need to be gentler, slower, with adequate foreplay if you are new to this.
