Program memory question (working dispite insufficient memory)
In your example you're not out of memory, you simply haven't allocated enough memory to hold the string. The remainder will end up in a memory area that's available to the processor but the compiler isn't aware of. While it may not cause a problem with this simple example in practice it can overwrite other variables and memory areas and should be avoided.

Also as Majenko mentioned in a comment you may want to take a look at snprintf which is a safer version to use because it also includes a parameter to specify the buffer length. Not all PIC compilers support it but if your one does the syntax would be:

snprintf(ahimouz, sizeof(ahimouz), "%s %s", we_are_display, "5");


That would prevent the possibility of other memory areas being overwritten, although it would also only display h because your buffer size is only large enough to hold a single character plus the null terminator.