Well, generally speaking, it is very normal to have this kind of symptom. As we know that when you are high, your emotion is also high. So it will irritate the nerve system and even make the blood pressure higher. In this way, the blood will flow to the eyes and make the bloodshot to eyes. At that moment, you will find your eyes become red. It is just one kind of condition, so do not too worry about it. But I have to remind you that if you are a person who has high blood pressure, you are not supposed to be high, for this can lead to be dangerous for you. Anyway, just be careful.