A320 flight crew reported a go-around due to unstabilized approach.

Narrative

During the approach into ZZZ we were given vectors onto final above the glide slope; this combined with us being empty led to having a tough time getting down to join the GS the usual way. I clicked the Autopilot off to manually push the nose over and attempt to capture. I quickly realized that we would not have made it to the GS and configured in time to be stable so I pushed to level off and told the First Officer (FO) to report going missed. He made the call and I pushed to level off at ~1200 ft. Only being at flaps 2 and still +1000 ft I intended to suspend the approach and not do a full go-around. I commanded gear up and a few moments later we received the too low gear aural alert. A few moments later we received it again and I pushed the thrust levers to TOGA to initiate the go-around in the FMS. We received another too low flaps alert soon after. I noticed the speed climbing; called for flaps 0 and then as the speed continued to climb I initiated the climb from ~900ft using the side stick as I had turned the Autopilot off. We climbed up to the altitude assigned in the go around and returned to ZZZ without any other issues.I had lost situational awareness and was commanding the airplane as if the Autopilot was on which led to an undesired aircraft state.