Only 1 leaf is droopy what gives?

Have this clone of Jack something that I planted yesterday. Everything is going fine except one leaf is drooping from a branch. I took a few pics but u cant really tell from the pic. It is moist and green but seems like the one solo leaf blade is dying. It is the top most middle leaf.

All the rest of the leavs are solid. I dont know how old the plant is but it has about 7 nodes already.

Please excuse my newbie behavior I am trying to read as much as i can but this seems like an emergency to me.

you're worried about ONE leaf ? Let er grow.

the nr1 newbie advise, should be, relax dont worry and dont get your panties in a bunch over nothing.
its like a teenager looking into a mirror and seeing his first pimple and deciding his life is over.

the leading cause of death among plants of newbies seems to be, seeing some tiny thing, totally panicking over it and trying absolutely everything without a clue as to how or even properly do it and then killing the plant (which in all likelihood would have been just fine if just left alone (well apart from regular watering and feeding and providing light and moving air (lol and protection from fools)

the turning point for me as a cannabis grower, was suddenly noticing how much better the houseplants seemed to be doing than the cannabis which i fuzzed over while for the houseplants i practically did nothing (lol just fed and watered them when i saw they needed it. which wasnt often)

couldnt tell more without seeing some pix, sounds more like some accident having happened last you were around the plants than some other problem. though i cant remember having seen this.

but then again, rant above or not, i havent grown That long, just 4-5 years. probably closing on 5, maybe someone will come along with a better info, but i still think its nothing.

depends on how old the clone is,how the root system is developing...then the basic questions..lights,nutes,grow area?
just one leaf drooping isnt much for concern...unless it gets worse.for most first time or new growers its a under or over watering issue.
do some research and about any issue can be found by simply googleing what the issue is.
you gonna find 30 people on here that will give you 30 different answers.instead of having others figure out what the issue is...use process of elimination and figure it out on your own...it will benefit you in the long run.most basic plant problems can be found easily...just watch and read your plants.

Thanks for the responses guys, the leaf seems to be standing back up, but it is curled and is taking on a darkish color. I havent done anything to the plant since its been drooping so I'm hoping it will just fix itself.

Now the leaf is fully back up but has completely turned yellow and the leaf next to it has a yellow spot. I raised the light a little bit in case it was suffering from high heat,but im only running 150watts so i didnt think it would be an issue.