The rollout of Obamacare may have been a colossal mess but Americans haven't seen anything yet – the real problems start Jan. 1, according to Doug Cote, U.S. chief market strategist at ING Investment Management.

"There is going to be a lot of wailing and gnashing of teeth when this is actually implemented," he predicted in an interview with Yahoo.

Cote predicted than when more tenets of Affordable Care Act (ACA) go into effect on January 1, and Americans start expecting care, there may be more shoes to drop.

Editor’s Note: Retirees Slammed with 85% Pay Cut (New Video)

"It's already been rocky . . . there are going to be a lot of after-effects that I don't think are appreciated."

Cote questioned whether some people who believe they have enrolled in Obamacare are actually registered due to ongoing computer glitches. And he predicted many people will be stunned when they find out how high their deductibles actually are.

He is also worried Obamacare will harm the economy and kill jobs for small businesses whose owners will find themselves beset by uncertainty and higher employee health costs.

"What it does is restrict the private economy," he said of the ACA.

"Uncertainty for doctors. Uncertainty for hospitals. Uncertainty for individuals. Uncertainty for businesses. That's what we're talking about," Cote told Yahoo.

He predicted insurance companies participating in Obamacare will not attract enough healthy policyholders and will have to recalculate their actuarial tables, resulting in even higher costs for patients.

The deadline to sign up for insurance under the new law for coverage beginning Jan. 1 was extended to Dec. 24, The Wall Street Journal reported.

"Anticipating high demand and the fact that consumers may be enrolling from multiple time zones, we have taken steps to make sure that those who select a plan through [Dec. 24] will get coverage for Jan 1," Julie Bataille, director of the Center for Medicare and Medicaid Service's Office of Communications, said in a statement, according to The Journal.

Editor’s Note: Retirees Slammed with 85% Pay Cut (New Video)

Related Stories:

• Rove: Latest Obamacare Changes Are Admission of 'Complete Failure'
• Polls: 77 Percent of Uninsured Don't Want Obamacare, Majority of Voters Want Repeal