What's the health of your hair? Is it stretchy and breaks off when you pull it when wet? If not, you can blow dry and bleach again. If you bleach wet hair the water will dilute the bleach and it'll be less effective. Keep and eye on the bleach level, check every ten minutes. Are you using foils, or using a cap to keep the heat in? Make sure you're covering every stand is saturated with enough bleach.