Agree with RatherBeFlying - if in doubt, there is no doubt - go round, settle down in the circuit and try again. You obviously 'got away with it' this time, and no doubt learnt from the experience, but as you say yourself, you had trouble maintaining speed (and height) and I would therefore gently suggest you were not in complete control.
And don't worry about hitting the odd block - it happens to everyone at some point. If you give up, you are never going to get through it! Keep at it - the more practise you get, the more natural it will become.