Tennis elbow is an overuse problem affecting tendons on the outside of the elbow. Pain with gripping or wrist extension is a reason to seek assessment rather than diagnose yourself from an article.
Contributing factors can include arm-dominant swings without trunk rotation, late or off-center contact, unsuitable racket weight or tension, and sudden increases in practice volume.
Management may involve light wrist-extensor strengthening, controlled lowering exercises and equipment review. Exercise loads should match your symptoms and professional advice. During an acute flare, reduce aggravating play rather than repeatedly playing through pain.