Do sports (at home, if you feel more confortable) but 3x 30min/week. Eat more greens, oilseeds, fresh fruits and food rich in magnesium such as: raw spinach, fish, beans, lentils, avocados, brown rice, bananas, figs and chocolate. If you have a pet, cuddle with it more often and take care of it. It will make you shift your focus from anxiety to something else. Try to catch the sun everyday for 10mins. Check your levels of vit D and B12 (adjust with supplements if needed). Yoga, you can find plenty of stuff online. Mindfulness meditation, it’s not hard, stick to it. When you feel anxiety, let it come, don’t fight against it. Take deep breath (inhale for 6 seconds, hold for 2, exhale for 6. Do it again). Just observe how tense and how bad you feel over nothing. Meditation can help to stand back. Sleep enough (7 to 9hours/night). Quit smoking and avoid drinking alcohol. Smile. Smiling, even for nothing, tricks the mind and releases happy hormones. Learn to manage your anxiety, it’s always going to be there because it’s a normal mechanism of protection but don’t let it rule you anymore. You are not alone.

Consult a doctor he can differentiate it

If ur vit B12 level came as so low then u can think of it. In both circumstances u can face same symptoms.

Madam, It's Indeed very Difficult to check at personal level At personal level you can take adequate dose of Vitamin B12 for 2-3 weeks and see the difference or else get your B12 tested however clarification based on clinical signs is possible thru visiting Psychiatrist