Do I have a problem with substances? What do you all think?

[InterestingFACT]

To echo what has been stated above, it sounds like opiates (heroin) are your drug of choice. While alcohol and pot may not be negatively affecting your life, you can't hope to carry on with your opiate use without a negative impact--even if you're not feeling it now, your first hardship in life could send you spiraling down a dark path, as you turn to substances to avoid your problems. A reminder: many people (I was tempted to say everyone, but must concede that some people are naturally self destructive in this way) can moderate their drug usage in the good times. It's when life isn't so great--when you've lost your job, or your wife leaves you, or a friend dies--that these things become problems. It's up to you to discern whether opiates could become a problem in poor circumstances, though my bet, based on what you've explained, is that they would absolutely become a problem in poor circumstances.

As for the alcohol and weed--you don't seem to have a problem with them at the moment. But there's a danger in giving them a free pass: giving up opiates, just to turn to alcoholism, is not a solution. Be wary not supplant one addiction with another.