Antonyms for the word "was apprehensive of" would be confident, reassured, composed, calm, secure, assured, and comfortable. If you were confident, you would have no need to feel apprehensive. If you were reassured, you would have received information or evidence that provided relief from your anxiety. If you were composed, you would be calm and cool-headed, showing no signs of nervousness or fear. If you were calm or secure, you would be free from anxiety and doubt. If you were assured, you would be confident about something. If you were comfortable, you would be at ease and relaxed, with no stress or worry.