Macam tu lah biasanya masa anak baru recover dari selsema ke demam ke, immune system dia still working hard maka bengkak lah lymph nodes dia, a few of us mums went through the same thing dengan toddlers, especially kalau frequent infections macam yours. The fact that the doctor reassured you and is monitoring dengan antibiotics is good sign, but since it's been 1.5 months sekarang and now ada groin nodes pulak, I think it's worth pushing for a proper blood work or referral to paediatrician just untuk peace of mind, bukan untuk scare you, but as moms kalau rasa something's off, better to get it checked thoroughly rather than just pantau. The snoring and big tonsils boleh jadi separate issue, maybe ask the doc about that too. Keep trusting your gut lah, if you're this worried, ada hak you untuk minta second opinion or further tests, no harm done.