Do you have an automatic? If so have to looked at buy a transmission mechanic. Sounds like your due for a rebuild.
Check your transmission fluid immediately. I've seen cars not shift out of 2nd b/c the fluid was low. Filled it back up and it ran fine. Others, took too long to fill up the fluid and the tranny needed a full rebuild.
A transmission that slips is one of the tell-tale signs that a transmission is nearing failure and may already be at the point where one or more gears will not work at all. GoECM.com
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