I have a 27’ above ground pool, sand filter, and single speed Hayward pump (pics attached). I got the pump as a hand-me-down from my aunt and uncle, so it’s likely old 
Last summer, the pump worked fine. It ran on a timer, would click on/off manually as well, maintained speed, always filled with water, etc.
Upon opening the pool this summer, I noticed that the on/off switch wouldn’t “click.” So it would turn on when I pushed the switch but would sometimes turn off when my finger let off the button. I would have to push it hard and then it would stay on (but no satisfying “click.”)
Last week, the basket in the skimmer was askew and the pump was running without water for an hour or so. Worried that damaged it because:
REAL ISSUE- the past two days, when the pump is turned on, it will begin to fill up and “whoosh” like it’s revving up to full speed but then it subsides and the pump empties, with only a trickle going in from the skimmer. All suction seems gone. If I wait a couple of minutes, it will “whoosh” again, but same cycle repeats. Therefore, our pool water is not circulating and we can’t vacuum, etc.
Am I missing something or is this a dreaded “get a new pump” situation?
Thanks I’m advance for all your help! Love this forum!

Last summer, the pump worked fine. It ran on a timer, would click on/off manually as well, maintained speed, always filled with water, etc.
Upon opening the pool this summer, I noticed that the on/off switch wouldn’t “click.” So it would turn on when I pushed the switch but would sometimes turn off when my finger let off the button. I would have to push it hard and then it would stay on (but no satisfying “click.”)
Last week, the basket in the skimmer was askew and the pump was running without water for an hour or so. Worried that damaged it because:
REAL ISSUE- the past two days, when the pump is turned on, it will begin to fill up and “whoosh” like it’s revving up to full speed but then it subsides and the pump empties, with only a trickle going in from the skimmer. All suction seems gone. If I wait a couple of minutes, it will “whoosh” again, but same cycle repeats. Therefore, our pool water is not circulating and we can’t vacuum, etc.
Am I missing something or is this a dreaded “get a new pump” situation?
Thanks I’m advance for all your help! Love this forum!