Hardy-Weinberg is a null model: if a population is large, mates at random, and feels no mutation, no migration, and no selection, then allele frequencies never change. Genotypes just settle into the ratio p² : 2pq : q² after a single generation and stay there.
The whole point of the null is to notice when it breaks. Selection, migration, and mutation each push the allele frequency p in a direction — that is evolution. Genetic drift, the sampling error of a finite population, moves p at random; the smaller the cage, the wilder the wobble, until pure chance can fix an allele.
Inbreeding is the odd one out: it drains heterozygotes and piles up homozygotes, so a χ² test flags a departure from p² : 2pq : q² — yet p itself never moves. Which quantity changes tells you which condition broke.
Something in the simulation stopped unexpectedly — the lesson continues without it. You can move on; nothing you did was wrong.