Conditions For Entering Paradise or Hell?

If I've done slightly more good deeds in my life than bad deeds, am I more likely to go to Heaven, and vice-versa? And does the number of good or bad deeds you commit determine your level in either Heaven or Hell?

The smallest of all good deeds are counted as the biggest good deeds, but you can't tell if you're going to heaven or hell, that's only for Allah to decide