Problem with ESP8266 and Thingspeak

Hi guy,
As the title, I am trying to communicate with Thingspeak using ESP8266-01 connected via 3.3V USB-TTL adapter. And I follow this one: ESP8266 AT COMMANDS THINGSPEAK COM - YouTube

I connect the ESP and adapter like this way:
ESP Adapter 3.3V Battery
VCC +
GND GND -
RX TX
TX RX
CH-PD +

I use serial monitor of Arduino IDE to send AT command to ESP8266-01, I can connect to my home access point, but I cannot change the value from my Thingspeak channel. Here are the commands and responses:

Note that I have a little diffrent from the Youtube Tutorial, I use the AT+CIPMUX=0 (Single TCP connection instead of AT+CIPMUX=1 for multiple connection) but this is not the problem.

AT

OK
AT+RST

OK

ets Jan 8 2013,rst cause:4, boot mode:(3,6)

wdt reset
load 0x40100000, len 816, room 16
tail 0
chksum 0x8d
load 0x3ffe8000, len 788, room 8
tail 12
chksum 0xcf
ho 0 tail 12 room 4
load 0x3ffe8314, len 288, room 12
tail 4
chksum 0xcf
csum 0xcf

2nd boot version : 1.2
SPI Speed : 40MHz
SPI Mode : QIO
SPI Flash Size : 4Mbit
jump to run user1

rlŽ‚ÿ
Ai-Thinker Technology Co. Ltd.

ready
AT+CWJAP="xxxxxx","xxxxxxxx"

OK
AT+CFSR

ERROR
AT+CIFSR

+CIFSR:APIP,"xxx.xxx.x.x"
+CIFSR:APMAC,"1a:xx:xx:xx:xx:xx"
+CIFSR:STAIP,"xxx.xxx.x.xxx"
+CIFSR:STAMAC,"18:xx:xx:xx:xx:xx"

OK
AT+CWJAP?

+CWJAP:"xxxxx"

OK
AT+CIPSTART="TCP","184.106.153.149",80

CONNECT

OK
AT+CIPSEND=44

OK

GET /update?api_key=5MP75L84PK1QHP4D&field1=44
busy s...

SEND OK
CLOSED
AT+CIPCLOSE

ERROR
AT+CIPSTATUS

STATUS:4

OK

For all who is following this,
I've found the tutorial: Tutorial: IoT Datalogger with ESP8266 WiFi Module and FRDM-KL25Z | MCU on Eclipse
I can now communicate with Thingspeak. But there are somethings really weird! The wiring is still the same. But I change the way of command:
(My firmware version is: 00170901)
(already connected to access point)
AT+CIPMUX=0
AT+CIPSTART="TCP","184.106.153.149",80
AT+CIPSEND=46
GET /update?key=xxxxxxxxxxxxx&field1=50

the serial monitor did not respond until I sent the "AT" command to check if it was alive! So funny that, the ESP responded:
busy s...

SEND OK

+IPD,1:2
OK

OK
Unlink

And the data of Field 1 in my Thingspeak channel is changed to 50, exactly what I want.
But I cannot explain anything about this. Does anyone have anything more about this?