Will I be drug tested at my second hearing?

Probably not. If you are placed on probation, however, you will likely be tested at some point.

Unlikely, but not impossible, particularly if you demonstrate there may be a reason for the court to be concerned. Stop doing things you ought not be doing. Life will be easier if you do.

It is possible you will be tested for drugs/alcohol at your next hearing. You have not provided enough information for anyone to give you a good idea of whether this is a possibility. If you have not already done so, you need to hire counsel to represent you in this matter.