diff --git a/tiny-debug.lua b/tiny-debug.lua
index 0b4ef8c..278804b 100644
--- a/tiny-debug.lua
+++ b/tiny-debug.lua
@@ -48,7 +48,7 @@ function tinyDebug.getEntityAgeMs(entity)
     if ENTITY_INIT_MS == nil then
         error("trackEntityAges() has not been enabled!")
     end
-    return entity[ENTITY_INIT_MS]
+    return getCurrentTimeMilliseconds() - entity[ENTITY_INIT_MS]
 end
 
 function tinyDebug.warnWhenNonDataOnEntities()
@@ -87,7 +87,7 @@ end
 
 function tinyDebug.throwOnUnusedEntities()
     ---@return boolean
-    local function entityMatchesASystem(world, entity)
+    local function entityMatchesSomeSystem(world, entity)
         local systems = world.systems
         for i = 1, #systems do
             local system = systems[i]
@@ -106,7 +106,7 @@ function tinyDebug.throwOnUnusedEntities()
         local el = world.entities
 
         for i = 1, #el do
-            if not entityMatchesASystem(world, el[i]) then
+            if not entityMatchesSomeSystem(world, el[i]) then
                 unmatchedEntities[#unmatchedEntities + 1] = el[i]
             end
         end