Will Final destination other than work location cause problem at Port of Entry?

[santoshthakur]

I will be coming to US on H1B visa and my client location will be San Fransisco. But I wish to travel to St. Louis first , stay with my brother for a week and then only leave for San Fransisco. At the port of entry, will I be questioned as to why am I not traveling to San Fransisco? Do they check where my connecting flight is going? Any inputs will be highly appreciated.