As long as you temp pretty close to the time you wake up thats okay. 5-15 mins is not going to make a huge difference. Make sure though that your thermometer is lying beside you bed so that you dont move too much before taking your temp. Record it right away.
When you get your eggwhite mucus it will litterally look like RAW egg white. It should be pretty clear, stretchy, a bit watery and in abundance.
BD'ing around this time of your cycle cant hurt!!!!HAVE FUN!!!!!
baby dust to you