Has anyone had Herceptin/Hylecta side effects?

Hi does anyone take Herceptin /hylecta the subcutaneous injection for HERS positive. I will start getting this on October 16 .I was on biosimilar trazimera and did fine for 6 months and then they stopped making the formulary at Cancer Center they put me on Kanjinti and I got hives on both legs and pins and neddle sensation in legs and head and nose was itching so bad so I had to take 5 days off prednisone and I am ok now.Pray that I won't have an allergic reaction to Herceptin/hylecta. I want to finish if possible but at same time I am afraid at going thru and oh course have concern about my heart since this medication can cause heart issue and lung issues but so far after 3 echocardiogram while on targerted therapy I am ok heartwise.