Do not overdo yourself. Our brain needs some time to process new information in our head. Learning HTML and/or PHP cannot be done overnight or in one day. So take some break and let the information settle in your brain. Fifteen minutes to one hour a day is enough for us to go forward. Like any other leaning endeavor, overdoing will do no good to us. Learning is not effective in a short span of time. If we push ourselves very hard, we might end up losing our health, so what's the point. Health is our most precious wealth. So take it easy buddy.