My best guess would be that the cooling system in your lappy is clogged which can cause your system and wifi to go slow - the PC internals detect when they are getting hot and "pause" to prevent damage.
My boss had a 2004 Sony Vaio laptop and the fan would go all the time. He finally relented and took it apart, removed 10 years of dust from the fans and they stayed quiet all the time after that.
I did the same on my Dell XPS M1530 when the fan stuck on - and I live in very clean house (I have Asthma as does A-Junior so it is cleaned regularly). The cooling system consisted of copper pipes and a fan but the intake to the fan was blocked - cleaning from the inside fixed it (and removed a giant dust bunny) plus replacing the thermal paste which I disturbed removing it. Totally silent fans too.
This is the cooling on a M1530.
I also have an SSD. Mine is about 3 years old and no problems at all - and I stress it with Virtual Machines and Database work, it is in the PC I'm typing this fr...
Heat can kill them though, so a cleanout might be beneficial.
If you post the model I can see if there is a dismantle / reassemble tutorial - there is for most models including Mrs A's old crappy HP "salesman" laptop which I wish I hadn't fixed.
EDIT - your recent reprieve might be just that - maybe the dust got dislodged but it will be back.