Welcome Alex 
I’m not recovering from heroin myself but if you search “heroin” or “opiates” (or similar terms) in the search bar you’ll find lots of threads about it. Opiates are - if you’ll excuse my language - a total f*ckstorm and you’ll see that in the stories on those threads but you will also see that people can and do recover from it, and you can too.
You need help. (All of us did, and do - we all need help.) There’s no shame in needing help; it’s a basic human truth. Whether you’re learning to play baseball or you’re learning to play life sober (and trust me, living a healthy life, sober, has rules and best practices and other stuff you need to learn, just like any game!) - when you’re learning, you need help. (And life is always about learning, one day at a time 
)
For me, meetings made a huge difference. When I joined a group is when my recovery really started to gain momentum. For heroin and other opiates, NA is good:
https://www.na.org/meetingsearch/
There are also meetings online:
It’s also helpful to check in here on Talking Sober. I come here every day, read and comment, and if I have the “addict voice” talking to me (those times when your brain starts saying “it’s ok, just one time” - we all have that now and again), I come and check in here. It’s kept me safe many times. Something about writing it out is helpful:
Checking in daily to maintain focus #39
You do whatever you need to do to stay sober. I like to say, you have permission to do anything that’s safe and legal, to stay sober. For example: go to 4 meetings a day (why not? It’s a safe place), eat 2 boxes of chocolate, take 4 hour walks listening to angry music, visit 5 museums in a day, cancel plans with people if you think it will tempt you (that is totally fine - your sobriety comes first, and real friends will understand), etc etc.
Remember: you’re a good person and you deserve a safe, sober life where you can be your full self.