Terrible 22 Mile Run

Still not sure why I ran that bad today. Maybe not enough sleep last night?
I know I should bring one more gel today. And should run with others from
miles 11th to 14th. I blamed the running after miles 19th to the gel.
I felt like that I can not run after that. I will try to run 20 miles next week
until I can run steadily faster(around 9:30 if possible). Here are the splits:

Split	Time	Distance	Avg Pace
Summary	3:53:34.6	22.00	10:37
1	10:13.6	1.00	10:14
2	10:09.2	1.00	10:09
3	9:20.4	1.00	9:20
4	10:01.7	1.00	10:02
5	9:11.4	1.00	9:11
6	8:46.1	1.00	8:46
7	8:32.5	1.00	8:33
8	7:47.4	1.00	7:47
9	8:50.5	1.00	8:51
10	9:51.0	1.00	9:51
11	9:32.3	1.00	9:32
12	10:53.0	1.00	10:53
13	12:51.6	1.00	12:52
14	12:00.5	1.00	12:00
15	10:21.4	1.00	10:21
16	11:17.6	1.00	11:18
17	11:12.7	1.00	11:13
18	11:30.3	1.00	11:30
19	12:24.2	1.00	12:24
20	12:22.7	1.00	12:23
21	13:37.0	1.00	13:37
22	12:43.9	1.00	12:44
23	:03.6	0.00	12:27