Lots of people have encounters with the same sex like you are describing and wind up settled in their sexuality with the opposite sex. Sometimes the kind of encounters you had leads to their realization they are bisexual. Who do you love? Who turns you on? Just keep track of that without judgement and it will lead you to the definition you are seeking.
Ok this is what I find ofter. People having sexual encounter with same gendered person and question their entire identity. The answer is simple: No honey, you're not.
If you feel sexual attraction to boys exclusively: You are straight. If you harbour sexual attraction for girls aswell: you are bisexual.
Also there is something called sexual attraction, and emotional attraction. Do you find yourself attracted to female body or do you think you can fall in love with a girl? Only cause the encounter felt good doesn't mean your whole sexual preference changed. You maybe really enjoyed the closeness. You also avoided genitalia. Are you attracted by female genitalia? Do you think you can work yourself around them, stimulate them and to satisfy your same gender partner? If the answer to both is no: you're neither bisexual nor lesbian.