Starting to freak out

This last week I am starting to freak out about my training. I feel like I haven't done enough and I have just about run out of time. I am going to push these last 3 weeks and hope that I have done enough to get me through. I have picked up a couple books about not worrying about things I don't have control over, but I have invested so much time, how can you not worry. Augh. I finally realize this past Sunday that this Ironman is going to be hard. I did a 2.5 Bike/1.5 run/1.5 Bike/30 Run. I was exhausted after that. That is only about half of what I need to do and add a swim on top of that. I wish I could have another 4 weeks to train. I have 2 6.5 hour bikes, 1 5.5 hour bike and 3 2.5 hour runs left along with my normal during the week workouts then taper time. The time is coming up so fast. I can almost smell the Ohio.
Update on the foot: I got my orthotics last Thursday. I ran 45 min on them Thursday night and felt really good. No pain and most importantly, no pain the next day. I ran again Sunday for my 2 hour run. Stupid me, I didn't wear socks so I have a huge blister in the arch of my foot. That skin is not use to having anything touch it. The run went good. I attempted to run again last night, but my job distracted me from drinking water all day so I was very tight and crampy for the run. I ended up only running for 20 min and walking for 40. My legs felt very heavy. I am sure there was some fatigue from Sunday, but it didn't feel like it normally does. I am sure I was tired, but the no water thing really hurt. Tonight I am getting in the pool for an hour and a 2 hour bike to follow. Tomorrow a 30 bike/30 run followed by a softball game. I am doing my long bike Friday since I will be out of town and not able to do it Saturday so that will be my day off. I will be eating very bad food all day at the family reunion. Yum! Sunday a 2.5 hour run. Probably will break it up into a 1.5 hour run/30-60 bike/1 hour run.