The immigration consequences of convictions depend on the exact language of the statute under which the conviction took place.
You need to retain an experienced immigration lawyer to review all the facts, including the court disposition and the charging documents, in order to advise you, and handle the case.
J Charles Ferrari Eng & Nishimura 213.622.2255 The statement above is general in nature and does not constitute legal advice, as not all the facts are known. You should retain an attorney to review all the facts specific to your case in order to receive advise specific to your case. The statement above does not create an attorney/client relationship. Answers on Avvo can only be general ones, as specific answers would require knowledge of all the facts. As such, they may or may not apply to the question.
You should definitely retain an immigration attorney. Sometimes misdemeanors cause problems for immigration applications, other times not. What matters is not whether the offenses were Class B or Class C, but the specific nature of the offense, whether you served any time and whether you committed the offenses at the same time or not.
If you are lucky, you won't be found inadmissible for having criminal convictions. If you are not so lucky, then you will need a waiver of inadmissibility.
I strongly advise you to retain an immigration attorney. Your case is complex.