Noob question: Why is Interactive Brokers telling me I'm generating more than $30 in profit with my HMY May calls, if my average price and the contract's last price are the same?

IBKR is retarded when it comes to showing unrealized profits, then use the ask-bid difference in misleading ways. Your guaranteed unrealized profit is = Current bid - Your Avg - Commission.

So they are retarded on purpose about the most important feature on their platform? Good to know