Twins?

[cookingmama02]

Negative tests 2 weeks ago
Intrcourse 4 weeks ago
Missed period April and may
No HCG in blood 3 weeks ago
Clear blue digital showing 3+ today?
Doesn't make sense

April missed period = coincidence/ maybe no ovulation
May missed period = pregnant
2 weeks ago not enough HCG to trigger the test
3 weeks ago ovulation and fertilization just happening, no measurable hcg yet
4 weeks ago sperm introduced which stuck around for a few days before ovulation.

Something like that would explain your 3+ weeks positive test!
The weeks count on those things is not super accurate. Ask for a dating scan.