I had sick pay included in my wages why was i taxed at a higher rate?

Where are you seeing on the W-2 that the sick pay was taxed at a higher rate?

If your employer paid for the policy then the amount would be included in box 1 of the W-2 and taxed at the same rate as the rest of your wages.

See this TurboTax support FAQ for sick pay - https://ttlc.intuit.com/turbotax-support/en-us/help-article/income/third-party-sick-pay-taxable/L1AEnNiyA_US_en_US?uid=m05jyusy

If this is a lump sum income, it is often withheld at a higher rate due to IRS rules on lump sum payments.  Your actual income tax due is calculated on your tax return at the end of the year, based on all your income and deductions, and if you were over-withheld, the difference comes back to you as a tax refund.