I do the opposite!Check the air with the valve stem located near the top.
Is that a brand name... "Slime" or a generic term? I've just switched to tubeless and the dealer said in his experience the best sealant is now "Finish Line". So I've got that in my tires, but now I see the reviews for that are all over the map, from people raving about it to those who hate it. But I guess I'm stuck now until I need to remove the tire and clean it out. I did find out from the reviews though that the dealer seems to have put in half the recommended amount. So I'll have to buy some of the same stuff and add it, as I'm sure different products couldn't be mixed together.I started using slime in my bikes about 5 years ago. NO problems to report in that time span.
I ordered a bottle of Slime without having seen your reply. And just by luck, it's the right one "Tire Sealant" as opposed to "Tube Sealant" that I'd ordered. I don't know if I should chance adding it to my tires which have (not enough, according to the manufacturer) of the Finish Line sealant the dealer installed. Probably not a good idea to mix different sealants. So I'll see if I can buy/order some of the FL sealant just to top the tires up. And then when I have to remove the tires for any reason, I'll clean them out and use Slime next time.Yes, Slime is a brand. There are two types, if you want to try it. It comes for tires with tubes and for tubeless tires. Get the right kind for you needs.
Thanks for your advice. I'm not afraid of flats but I'd rather not have them! In my lifetime I've probably fixed 50+ flats but never (until now) on a bicycle with tubeless tires and rims. I was really surprised at how difficult it was to get the tire off the rim and the tire irons that served me well for many years almost broke. Now I've got a better tool so it'll be easier. But I still prefer not to have a flat, especially now with sealant inside the tire. I am carrying a spare tube just in case, plus latex gloves, but don't carry a rag or paper towels. I'd rather not have to wipe the sealant out before putting in a tube if I'm on the road somewhere.I think I saw a You Tube comparing a few sealants. I can say there are definitely a lot of strong opinions about brands and even whether any of them are any good.
Flats are almost inevitable if you ride enough. They're nothing to be afraid of. Just make reasonable preparations and take precautions.
To the extent I'd worry about you're situation at all, I'd get more FL when you get around to it, top up, be done.