'feeling fearful' is correct and can be used in written English.
You can use it when you want to express a feeling of fear or anxiety, though the context of the sentence matters. For example: After hearing the news, she began feeling fearful about her future.
a. Anxiousness: Intense feelings of nervousness, tenseness, or panic, often in reaction to interpersonal stresses; worry about the negative effects of past unpleasant experiences and future negative possibilities; feeling fearful, apprehensive, or threatened by uncertainty; fears of falling apart or losing control.
When you are feeling fearful, you need a team of people around you who will allay those fears.
Insecurity has left ordinary people feeling fearful and helpless.
I couldn't blame them; I was feeling fearful also.
Even though he was feeling fearful, he did not believe that he would be harmed.
As Week in China wrote in early 2012: "So if gaming revenues continue to surge this year … it's a safe bet that corrupt officials and savvy businesspeople are feeling fearful about the future and are getting their money out".
Perhaps you undervalue your gift for friendship, and worry unduly about how you come across in company, and thereby disguise your true feelings, fearful of rejection.
Those standing on the skateboard overestimated the steepness and also reported feeling more fearful than those on the box, indicating that fear and confidence also play into our perceptions of reality.
Other stakeholders reported feeling more fearful than optimistic about yet further change.
It can leave children feeling withdrawn, fearful and depressed, and can lead to involvement in drugs, alcohol and dysfunctional relationships.
Karen Finley, a New York performance artist, said that as a result, artists and arts organizations are "feeling very fearful" about invasions of their freedom.
