Thinking or feeling something with 〜気がする
Grammar: Conjecture » 〜気がする
気がする following a word or phrase ending with a verb, adjective, or noun, has the meaning of “I feel that ~” (「〜と感
There is a slight difference in connotation. 「〜と思
To express conjecture (推量
Mina proclaims she knows a shocking fact about being caught in the rain: it doesn’t matter whether you walk or run because you’ll get wet the same amount either way. Sanae says she heard running it better to avoid getting as wet. Mina says if it starts raining, she’ll walk, and Sanae has to run. Nao sees Makoto’s cat, Chito. She stops to pet the cat when she notices something. As thanks for Naho making him lunches, Kakeru gives her a jewel-encrusted hair clip. In her room later, Naho looks over the piece.Further Reading
Examples
Feeling running is better after all with 〜気がする

Feeling you've gained weight with 〜気がする

Thinking it cost more with 〜気がする
