One thing some ex jw's do not understand when first starting- yes, you must wrap (or use gift bag & tissue) if giving presents. Using the plastic bag from the store is not the same! buy the wrapping paper and if you don't understand how to wrap a present find a youtube on how to do it. However, if you are known to be an ex jw all will be forgiven and there will be much joy and astonishment that you are joining in all the festivities. If you are a non jw guy who hands something over in a plastic bag from the store you will look like a lazy so & so.
Also, timing- if you have agreed to some sort of gift exchange (at work or elsewhere) you gotta have the present there on time, not later. It looks like you forgot and the gift is only an obligatory after thought.
now have a very Merry Christmas and don't stress about things it's all in good fun.