Haha! Managed to do it thanks to your indications sachin, but with GridBagLayout.
SettingsManagerTab.panelForTweet1.setLayout(new GridBagLayout());
this.add(SettingsManagerTab.panelForTweet1);
SettingsManagerTab.labelForTweetPhoto1 = new JLabel(new ImageIcon(
SettingsManagerTab.class.getResource("/res/User1.png")));
final GridBagConstraints a = new GridBagConstraints(), b = new GridBagConstraints(), c = new GridBagConstraints(), d = new GridBagConstraints();
a.gridheight = GridBagConstraints.REMAINDER;
a.gridx = 0;
a.weightx = 0.1;
a.anchor = GridBagConstraints.LINE_START;
SettingsManagerTab.panelForTweet1.add(SettingsManagerTab.labelForTweetPhoto1, a);
SettingsManagerTab.labelForTweetUsername1 = new JLabel("@usuario1");
final Font contentFont = new Font(SettingsManagerTab.labelForTweetUsername1.getFont()
.getName(), Font.BOLD, SettingsManagerTab.labelForTweetUsername1.getFont()
.getSize());
final Font userFont = new Font(contentFont.getName(), Font.BOLD,
(int) (contentFont.getSize() * 0.7));
SettingsManagerTab.labelForTweetUsername1.setFont(userFont);
b.weightx = 1;
b.gridwidth = 2;
b.anchor = GridBagConstraints.LINE_START;
SettingsManagerTab.panelForTweet1.add(SettingsManagerTab.labelForTweetUsername1, b);
SettingsManagerTab.labelForTweetContent1 = new JLabel("contenido");
SettingsManagerTab.labelForTweetContent1.setFont(contentFont);
c.gridheight = GridBagConstraints.REMAINDER;
c.weightx = 1;
c.anchor = GridBagConstraints.LINE_START;
SettingsManagerTab.panelForTweet1.add(SettingsManagerTab.labelForTweetContent1, c);
SettingsManagerTab.labelForTweetHashtag1 = new JLabel("#demo");
SettingsManagerTab.labelForTweetHashtag1.setFont(contentFont);
d.weightx = 30;
d.anchor = GridBagConstraints.LINE_START;
SettingsManagerTab.panelForTweet1.add(SettingsManagerTab.labelForTweetHashtag1, d);