Inappropriate sexual behavior, as though I cannot control myself; could someone have spiked my drink?
Once or Often? If you are talking about a one time event, then depending on the setting and circumstances, it is certainly possible for you to have been drugged. If you are talking about something that occurs often, then you may be struggling with internal issues. If you are concerned about this it would be worthwhile to seek out a therapist to discuss and evaluate the situation.
Inappropriate Beh. If you have concerns about your inappropriate sexual behavior it may be that you are struggling with sexual addiction. Therapy can be beneficial in helping further help you find ways to be more in control of yourself.
Start with help. Start with your primary care doctor and explain the situation. He or she can guide you to help. If you don't have a doctor or insurance, start a search for mental health facilities in your area or free/low cost clinics. Most areas will have a place you can go. Admitting the thoughts/feelings you are having is the first step - go for it. You'll be happy you did.
Age/consent. One definition is legal, i.e., inappropriate sexual relations with minors. Another definition is by consent. Two people who are so engaged in sexual activity and one of them doesn't like it.