Specializing in Mental Health Nursing

Hello my fellow nurses;
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I have a dilemma. I am a new grad and with the current situation and the difficulty new nurses are facing, it has been difficult for me to land in job in a hospital. I have applied to over 300 hospitals in my area and to no avail an opportunity has come my way.

This is where my dilemma lies; I have accepted a part-time mental health nursing position in a nursing home this has been my first offer since I got my license in January and I accepted. The pay is decent, but more importantly it is a way of getting into and doing some kind of nursing. I have worked out an agreement with them that I can do regular nursing on an acute unity, in the nursing home where they have G-tube, vents, trach, etc and critically ills patients, and I have been doing that and learning a lot. . The director even said to me, if I wanted they have a full time nursing position, but for some reason I like the mental health peace and have decided to work part-time as a mental health nurse in this facility.

My question is, are there specific certifications I can take to enhance my skills as a mental health. I plan to go back to school next year and in enroll in graduate school to get my NP in mental health. But I was wondering what I can do in the mean time to break into mental health and sharpen my skills. Are there any classes or courses I can take.

Any nurses who specialize in mental health please share your experiences, ideas etc.