The above suggestion is very practical. Take the failure lightly.In a proper environment you will perform mutually satisfactory climax.
To enhance sexual stamina, you may do breathing exercises.
1 abdominal breathing.
2 Retaining breath
3Tandem breathing.
See the video on breathing , given above.
You may also google the words to get the websites.
It sounds like a lack of confidence or "beginner's nerves". Try not to worry about it beforehand, if you can. It can get in your head and you worry and then it happens.
Doing it in strange places (not in your comfortable place) can add distractions and awkwardness.
You're young.
It sounds normal.