As mentioned, the two convictions are a problem. The fact that you were eighteen does not matter, where you were charged as an adult. It is hard for people to face deportation realities. People who have lived in the U.S. with a greencard since the 1960s are deported. We also need to know if one of your parents may have become a citizen and when?
Your case is first covered by the Immigration Court. Above the Immigration Courts is the Board of Immigration Appeals. The Board of Immigration Appeals has nationally binding decisions. There is a Board decision that strongly suggests, but does not confirm, that you are deportable. However, it is very possible, even more than likely, that you are deportable.
This is why you need legal representation before you create more problems. Too many people mess up their cases trying to represent themselves. Once the first level is over, it is possible that the damage may not be undone. The Eighth Circuit can rule against you where you try to represent yourself.
If you pled guilty to two misdemeanor possession charges and were found guilty (not adjudicated a delinquent), then you really need representation. However, you are 'not entitled' to an attorney like criminal court.
The above is general information and does not create an attorney-client relationship.
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