Chances are... yeah. However I am no expert (yet) -- But no worries, it's a weed after all, so all should be fine. From now on, make sure the soil is dry before watering. Completely dry. Jus stick your finger in the soil like 2-3 inches deep along the side of the pot, and if its totally dry, water her a bit. I know I did the same thing, over watered my plant when she was just a sprout. Her growth was severely stunted. However, (I corrected a Ph issue I had also) and stopped drowning her, and now she's coming back to life with a vengance! lol.
Also don't give too many nutrients too quick, it could get "nute lockup" (or whatever its referred to as) and will also prevent your plant from growing at its normal rate. If you should always start at half the rec. concentration and slowly work your way up. If you need more step-by-step advice and tips, the main forum threads are very good.
Also if you enjoy organics and around the house stuff, I have a link you should check out, its a bunch of organic and chemical compounds/items found around the house that can be used for fertilizer, they even broke down the N-P-K concentrations. Hope this helps man!
http://www.onlinepot.org/grow/NPKCharts.htm
If I were you though, I would correct the watering issue first, let your plant re-bound a bit from that, then fix the Nitro def if that is the issue.
Good luck man.
PS. When you have nutrients in your soil, flushing with water binds to the fertilizer and gets absorbed into your plants. Therefore flushing only releases more nutrients-- worse thing to do if you have nutrient enriched soil.... Not sure if you mentioned something about nutrient enriched soil, I thought I'd throw tht in there to be safe lol. sorry -- real baked lol.