I would just wait and see. Secondary spikes generally have fewer flowers than the original spike so it won't be very heavy. Once the flowers are open, if you feel that they're drooping too much, you can remove the clip you have on the top of the stake and move the spike over so you can tie the secondary spike to the stake out about two or three inches from the main stem. Personally I don't think that will be necessary. The spike should support the 3-4 flowers without any problems. After all, in nature they aren't staked at all.