I think I am underweight for my age and height?

I am 20 years old and 5 feet 4 inches tall. I am only 110lbs. When I first started university last year I was 135lbs. Since having to walk everywhere and not eating properly or very much I lost 25lbs over the course of a few months. I think I am underweight for my age and height. Every time I see my parents they comment about how I am wasting away. I am constantly getting sick now too. Could it have something to do with my weight? I am not anorexic (I eat, just not all the time as I don't like cooking nor do I have time to cook), but I feel like I am under weight for what I should be. I am happy and confident with my body, but just concerned as my weight could be the I reason I am always sick.

Am i underweight for my age and height or am I just paranoid?
I think I am underweight for my age and height?
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