Week 17 is extremely tough for most cappers (myself included). Nothing to be ashamed about. It's tough to predict if/when players are gonna sit and if/when teams are going to get up for games with extra motivation going into the playoffs. I usually do pretty poorly this week as well in 4 past years of posting here. This is the first year I've actually hit this week. I'm the exact opposite, get smashed in the bowl games was on bama -13.5 up 28-0 in the first quarter and managed to lose with a kneel on the 6 yard line. College is not my thing. The best advice I've learned is in this week tend to play more first half's (when players aren't sitting), over/unders or teasers with teams you think will cover. And if you choose to play a full game make sure it's a team that isn't going to pull starters - ex. they have to win the game to make the playoffs and if you want to bet the dog shoot to pick the entire game because favorites who are in the playoffs normally sit starters.
Best of luck going forward!