week 5 day 3 and week 6 day 1

i did week 5 day 3 on saturday... it was SOOOO HARD!! i wanted to stop... but i kept going for some reason... 20 minutes at 5.0. i did week 6 day 1 yesterday and my shins were kind of hurting :(. the last 5 minute run was reaaallly hard...... running is really hard and makes me want to eat a lot of cheese.