If I were you I'd throw in a rest day Thursday or Friday, too. Rest is VERY important. A lot of people view it as something they have to do like a "punishment" almost, but your muscle fibers that have been all torn up in training need time to rebuild and get stronger, and that happens on rest days. If you are already feeling tired in the days before your long ride of the week, at the beginning of the season, imagine how it's going to feel when you ramp up, if you don't add in more rest.
I know- it's hard. But important!! All you do by overtraining is damage, and you run the risk of getting mentally burned out, too, and it's tough to recover from that.
Nanci
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"...I'm like the cycling version of the guy in Flowers for Algernon." Mike Magnuson