In episode 1 of Gundam Wing, after Wing Gundam was sent crashing down with a Leo on the bottom of the ocean, Relena sees Heero unconcious lying on the shore. When Heero woke up his helmet was removed and he immediately covered his face while asking Relena "Did you see my face?" as shown in this picture.
He then punched a button attached to his spacesuit and something on his chest exploded.
See in this video (sorry I just included Gundam Abridge-ning episode 1 dub parody of Gundam Wing)
What actually did Heero do?