It's been 4 months since my last period, is that bad?

Depends. 1. You could be pregnant 2. In the face of other symptoms- hot flashes- vaginal dryness- this could suggest peri-mennopause 3. Until menopause hits, cycles will be like an accordion, normal, shorter-then longer-then normal- then longer-then shorter interval until finally no more cycles -->blood testing including a fsh and amh may help clarify your ovarian reserve status.
See your doctor. Please see your physician at your earliest convenience.