guys help pls in conveyor object counting

Guys i m trying to count the no of objects passing in a conveyor belt. for that purpose i am using IR sensor. When sensor goes low it have increase the count by 1.
Now the problem is in the debugger mode it increments the count properly. but while displaying in LCD it increment the count twice...
And i want to know whether i had followed correct procedure.. since i am new to this programming field. i had include my code below

Code (Text):

1. P3   = 0x00;
2.     LED1 = 1;
3. /* LCD initialization */   
4.     InitializeLCD();
5.  
6.     /* Display project titles */
7.     DisplayProjectTitle();
8.    
9.     *ArrayBasePtr=&UserMessageStorage;
10.    
11.     EA   = 1;
12.     EX0  = 1;
13.     IT0  = 1;
14.          
15.     while(True)
16.     {
17.  
18. /* Serial bit transmissions */
19.         SerTx(TotalCount[0]);
20.         SerTx(TotalCount[1]);
21.         SerTx(TotalCount[2]);
22.        
23.                 ArrayBasePtr="  TOTAL OBJECTS  ";
24.         DisplayLCD(1,0,ArrayBasePtr);
25.         ArrayBasePtr=&TotalCount[0];
26.         DisplayLCD(2,5,ArrayBasePtr);
27.         TimeDelay(850);
28.         LCD_CLEAR();
29. void Extint0 (void) interrupt 0
30. {
31. //  IE0=0;
32.   value++;
33.   Count = value;
34.  
35.         UserMessageStorage[4]= Count/100;
36.         Count=(Count-(UserMessageStorage[4]*100));
37.         UserMessageStorage[4]+=0x30;
38.        
39.         UserMessageStorage[5]= Count/10;
40.         Count=(Count-(UserMessageStorage[5]*10));
41.         UserMessageStorage[5]+=0x30;
42.        
43.         UserMessageStorage[6]= Count%10;
44.         UserMessageStorage[6]+=0x30;
45.        
46.         TotalCount[0] =  UserMessageStorage[4];
47.         TotalCount[1] =  UserMessageStorage[5];
48.         TotalCount[2] =  UserMessageStorage[6];
49.  
50.         ArrayBasePtr="  TOTAL OBJECTS  ";
51.         DisplayLCD(1,0,ArrayBasePtr);
52.         ArrayBasePtr=&TotalCount[0];
53.         DisplayLCD(2,5,ArrayBasePtr);
54.  
55.         TimeDelay(850);
56.         LCD_CLEAR();
57.  }

thanks for you help

Increase the time delay after the interrupt code and try.