You may still be able to Protest!

The Texas property tax protest deadline is May 15th, unless you were noticed late.
(Some counties allow you to file online until midnight and in others your protest must be mailed and postmarked by May 15th)

Per the Texas Property Tax Code:

The deadline to protest property values is May 15. Or 30 days after the appraisal district mails notice of appraised value.
Please review your value notice to see if you are still eligible to file a protest.
Download the Notice of Protest Form Here