Welcome to RIU. It's a shame seeing your plants but it happens, don't let it discourage you. Especially when in a place where supplies are not easily accessible. You got some good advice about watering, PH, Epsom salts and egg shells. I won't add to that as you don't really need more advise at this point. See about getting a PH test kit of some kind, should be fairly easy. Sort out your watering habits and try to deal with the feeding issues. It may take some time but I am sure the folks here can get you dialed in. Good luck and happy growing.