My husband was also told “a couple of weeks”. He traveled extensively for work (including the US) around the world over almost 20 years, and had to provide additional details on all travel outside Canada for the last 15 years .. going back to 2008. That triggered the DS-5535. It’s a black hole due to the security checks that are sent to various US agencies to verify his profile (final clearance is requested from the FBI, CIA, DHS, ICE, and others, including Washington DC)
Until a positive response is received from each agency, the US embassy will not issue the visa