I think over-feeding P is going to be the least of your woes.
-Epsom salts will WRECK your soil if you use too much, and that's easy to do. Apply them as a foliar feed at 1/4teaspoon per quart with 1 drop dish soap as a spreader/sticker, mist lightly. If you do not see evidence of Mg def, lay off the stuff.
-Vigoro is not a cannabis food and that N number in the bloom fert will likely give your trouble; more so because sativas as a rule feed a bit lighter than indis. Give less than the bottle recommends and watch the plant for signs of hunger or burn.
-Bone meal in your soil is great but IMHO, pick organic soil supplements OR a liquid fert and stick with it. If you want to go with organics, you will need to do a good bit of reading to familiarize yourself with the basic techniques.