Are Bonds the next bubble?

Interest rates have been extremely low for a good 5+ years now.  And we know its because of the Fed keeping the discount rate at zero and pumping free money into the sytem.  But nothing goes on forever and I have to wonder is the bond market the next bubble.  Look at all the other bubbles on this chart, while bonds have just been moving upward over the last 30+ years.  Will we see 1% 30 year mortgages?  I really doubt it but there are 2.5% 15 year mortgages now.

Are bonds the next bubble?