I have been shaving with my straight for about two weeks. I'm getting BBS shaves everywhere except a few problem areas on my neck. What I've been noticing, though, is that somewhere around 30 minutes after my shave, I get red blotches all over my neck and cheeks. It lasts for maybe 30-45 minutes then goes away. I'm not noticing any real "irritation" feeling or anything, just this redness. Any thoughts?