Use trimmer instead of razor and avoid the blood spots.
I just want to say that it's good thinking. You're aware of the problem and you had the instinct that something isn't right. I concur with @robertroland, don't go with the irritated skin.
Yes, certain infections or diseases can be transmitted through skin-to-skin contact. it's best to let the skin heal fully and always use protection. Keeping things clean and using a proper shaving method or aftercare can also reduce irritation and risk.