It's difficult to not act desperate when you actually are in a somewhat desperate situation (for example it's x weeks/months until you won't be able to pay your bills).
I was told I was acting too desperate and lacked confidence, to which I countered... how can I not act desperate when I’ve been lonely for so long? (Of course the answer to that is to enjoy being alone/single first, but I was getting huge FOMO and envy during college-age years when everyone else seemed to be in a relationship and I wasn’t). In hindsight, breaking out of a negative feedback loop requires a lot of conscious effort, or else reality becomes a nonstop fulfilling prophecy.
Instead, focus. Calm down. Think about writing software and building cool products. Redirect your energy into enthusiasm and try to have a conversation about adding value to your potential future employer.