I read the first sentence on FB (I know, this is not the right place to look for perfect grammar) and would like to know if this is right:
I can't sleep well since last week
I thought a construction like this needs the present perfect 'have been':
I haven't been able to sleep well since last week
The person who wrote the first construction is a native speaker of English which is why I'm so confused. Is it slang or just another way of saying it?